WO2023197125A1

WO2023197125A1 - Electrostatic lens used for reducing defocus distance

Info

Publication number: WO2023197125A1
Application number: PCT/CN2022/086194
Authority: WO
Inventors: 黎琼奔; 李小波; 张文; 贾智慧; 桂文静
Original assignee: 华为技术有限公司
Priority date: 2022-04-12
Filing date: 2022-04-12
Publication date: 2023-10-19

Abstract

The present application relates to the technical field of electron optics. Provided in the embodiments of the present application are an electrostatic lens used for reducing the defocus distance and a multi-split beam charged particle system having the electrostatic lens. The electrostatic lens comprises a first lens allowing a first charged particle beam to pass through and a second lens allowing a second charged particle beam to pass through. The first lens and the second lens each comprise a first electrode layer and a second electrode layer which are stacked and insulated, and in addition, the first electrode layer of the first lens protrudes towards the outside of the electrostatic lens relative to the first electrode layer of the second lens. Thus, when being applied to a multi-split beam charged particle system, e.g., being applied to an electron beam lithography machine, the electrostatic lens can reduce the defocus distance of the first charged particle beam and the second charged particle beam by means of the configured protruding structure, and further enables a focusing surface of the multi-split beam charged particle system to be a plane, thus improving the scribing efficiency of the electron beam lithography machine.

Description

Electrostatic lens for reducing defocus distance

Technical field

The present application relates to the field of electronic optics technology, and in particular to an electrostatic lens for reducing the defocus distance, a multi-beam charged particle inspection system with the electrostatic lens, and a multi-beam charged particle mapping system with the electrostatic lens.

Background technique

Multi-beam charged particle systems are commonly used for microscopic imaging, electronic engraving, semiconductor process defect detection and mask inspection, electron beam exposure, etc. Since the multi-beam charged particle system uses charged particles, such as electrons, and these charged particles have wavelengths much smaller than ultraviolet photons, it can provide better resolution than optical systems composed of optical lenses such as glass lenses or plastic lenses. .

Figure 1 shows the structural diagram of an existing multi-beam charged particle system. The multi-beam charged particle system mainly includes a particle source 1, a collimator 2, a beam splitter 3 and a first focusing mirror 4. and a second focusing mirror 5 , wherein the collimator 2 , the beam splitter 3 and the first focusing mirror 4 , and the second focusing mirror 5 are sequentially arranged along the beam path of the charged particle beam generated by the particle source 1 . The particle source 1 here is a single charged-particle source structure, that is, it generates a charged particle beam. The collimator 2 expands and collimates the charged particle beam generated by the particle source 1. The beam expands The collimated charged particle beam is then divided into multiple charged particle beams through the beam splitter 3, and each charged particle beam is focused by the first focusing mirror 4 and the second focusing mirror 5 for imaging.

Figure 2 shows the virtual source obtained by expanding the collimator 2 and splitting the collimated charged particle beam by the beam splitter 3, and extending each charged particle beam in the opposite direction. As shown in Figure 2, virtual source 1 and virtual source 2 create a distance T along the emission direction of the charged particle beam to form field curvature. Therefore, there will be differences in the virtual source positions of each charged particle beam as shown in Figure 2. Phenomenon, in this way, as shown in Figure 3, the focusing surface after passing through the first focusing lens 4 and the second focusing lens 5 becomes a curved surface, which will seriously reduce the imaging resolution.

How to reduce the defocus distance and flatten the focus surface, that is, make the focus surface a flat surface, so as to improve the imaging resolution is a thorny issue currently faced in this field.

Contents of the invention

The embodiments of the present application provide an electrostatic lens, a multi-beam charged particle inspection system with the electrostatic lens, and a multi-beam charged particle mapping system with the electrostatic lens. The main purpose is to provide a system that can correct field curvature and reduce scattering. Focal distance defocus is an electrostatic lens that can flatten the focusing surface of a multi-beam charged particle system.

In order to achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

In a first aspect, the present application provides an electrostatic lens. The electrostatic lens includes: a first electrode layer and a second electrode layer, a stack of the first electrode layer and the second electrode layer, and an electrostatic lens between the first electrode layer and the second electrode layer. insulation; the first electrode layer includes a first part of the first electrode layer and a second part of the first electrode layer, the second electrode layer includes a first part of the second electrode layer and a second part of the second electrode layer, the first part of the first electrode layer and The first part of the second electrode layer is arranged along the stacking direction, the second part of the first electrode layer and the second part of the second electrode layer are arranged along the stacking direction; the first part of the first electrode layer faces away from the second part of the first electrode layer. The direction of the two electrode layers protrudes; a first hole penetrating the first electrode layer along the stacking direction is formed in the first part of the first electrode layer, and a third hole penetrating the first electrode layer along the stacking direction is formed in the second part of the first electrode layer. Two holes; a third hole connected to the first hole is opened in the first part of the second electrode layer, and a fourth hole connected to the second hole is opened in the second part of the second electrode layer.

In the electrostatic lens provided by embodiments of the present application, the first electrode layer has a first hole and a second hole formed therein, and the second electrode layer has a third hole and a fourth hole formed therein, and the first The hole is connected to the second hole, and the third hole is connected to the fourth hole. The first part of the first electrode layer carrying the first hole and the first part of the second electrode layer carrying the third hole can constitute a first lens, carrying the second The second portion of the first electrode layer carrying the hole and the second portion of the second electrode layer carrying the fourth hole may constitute a second lens. In this case, when different voltages are applied to the first electrode layer and the second electrode layer, the charged particle beam can pass through the connected first hole and the third hole to converge, and another charged particle beam can pass through the connected first hole and the third hole. The second hole and the fourth hole are used for convergence, thereby forming a multi-charged-particle beam and multi-optical column system.

If the electrostatic lens is applied to a multi-beam charged particle system, such as an electron beam exposure machine, and the first electrode layer is set toward the direction of the particle source in the multi-beam charged particle system, according to Gaussian imaging theorem

Among them, f in the formula is the focal length, U is the object distance, and V is the image distance. If the focal lengths f of the first lens and the second lens are equal, since the first part of the first electrode layer of the present application faces each other, The second part of the first electrode layer protrudes in a direction away from the second electrode layer. It can be understood that the first part of the first electrode layer is closer to the particle source than the second part of the first electrode layer. In this way, compared with the prior art, By changing the object distance U1 of the first lens and the object distance U2 of the second lens, the image distance V1 of the first lens and the image distance V2 of the first lens can be changed. Therefore, through the first hole and the third hole The distance between the focal point of the charged particle beam and the particle source is not equal to the distance between the focal point of the charged particle beam passing through the second hole and the fourth hole and the particle source. In this case, the electrostatic lens can respond to field curvature. Correction and compensation are performed to achieve the purpose of flattening the focusing surface formed by the multi-beam charged particle system. It can be understood that if the electrostatic lens is used in an electron beam exposure machine, the charged particle beams passing through the electrostatic lens can be converged at the required location. on the exposed wafer.

In a possible implementation manner of the first aspect, the first part of the second electrode layer protrudes toward the direction closer to the first electrode layer relative to the second part of the second electrode layer.

When the electrostatic lens is used in a multi-beam charged particle system, in the first electrode layer, the first part of the first electrode layer is close to the particle source relative to the second part of the first electrode layer, and in the second electrode layer, the second electrode The first part of the layer is closer to the particle source relative to the second part of the second electrode layer. In this case, the distance between the first part of the first electrode layer and the first part of the second electrode layer can be adjusted to the distance between the second part of the first electrode layer and the second electrode layer. The spacing between the second parts of the layer is designed to be equal or unequal.

In a possible implementation of the first aspect, the first part of the second electrode layer protrudes in a direction closer to the first electrode layer relative to the second part of the second electrode layer; and along the stacking direction, the port of the first hole is close to the third hole , the distance between the port of the third hole close to the first hole is d1, the distance between the port of the second hole close to the fourth hole, and the port of the fourth hole close to the second hole is d2, and d1 =d2.

In this case, when a first voltage is applied to the first electrode layer, and a second voltage different from the first voltage is applied to the second electrode layer, the field intensity distribution around the connected first hole and the third hole is equal to The field intensity distribution around the connected second hole and the fourth hole is basically the same, based on the relationship between focusing distance and electric field intensity.

as well as

Among them, F in the formula is the focusing distance, A is a constant, U _K is the kinetic energy of the charged particle beam when passing through the hole (in the same multi-beam charged particle system, U _K is a constant value), Δu is the two electrodes The voltage difference loaded on the layer, d is the distance between the two electrode layers. In this embodiment, since d1=d2, and furthermore, ΔE1 of the first lens and ΔE2 of the second lens are basically equal, so from the perspective of electric field intensity, the field curvature correction is basically the same. In addition, when the electric field intensity is basically the same, At the same time, the imaging effects are basically the same.

It can be said that in this embodiment, the field curvature is corrected by adjusting the object distance while ensuring that the field intensity distribution is basically the same.

In addition, in terms of manufacturing process, the same manufacturing process can be used to prepare the first electrode layer and the second electrode layer with the same structure, which further simplifies the manufacturing process of the electrostatic lens.

In a possible implementation of the first aspect, the electrostatic lens further includes a third electrode layer stacked on a side of the second electrode layer away from the first electrode layer, and the third electrode layer includes a third electrode layer A part is connected to the second part of the third electrode layer. The first part of the third electrode layer is provided with a fifth hole connected to the third hole. The second part of the third electrode layer is provided with a sixth hole connected to the fourth hole. The first part of the three-electrode layer protrudes toward the second electrode layer relative to the second part of the third electrode layer; and along the stacking direction, the port of the third hole close to the fifth hole and the port of the fifth hole close to the third hole The distance between the ports is d3, the distance between the port of the fourth hole close to the sixth hole and the port of the sixth hole close to the fourth hole is d4, and d1=d2, d3=d4.

In a possible implementation manner of the first aspect, the first part of the second electrode layer protrudes in a direction away from the first electrode layer relative to the second part of the second electrode layer.

It can also be understood that when the electrostatic lens is applied in a multi-beam charged particle system and the first electrode layer is arranged toward the direction of the particle source in the multi-beam charged particle system, the first part of the first electrode layer is opposite to the first electrode layer The second part is closer to the particle source, and the first part of the second electrode layer is farther away from the particle source than the second part of the second electrode layer. Furthermore, the distance between the first part of the first electrode layer and the first part of the second electrode layer is larger than the first part of the second electrode layer. The distance between the second part of one electrode layer and the second part of the second electrode layer, that is, the distance between the first hole and the third hole is greater than the distance between the second hole and the fourth hole. In this case, the distance between the first hole and the third hole is greater than the distance between the second hole and the fourth hole. The field intensity distribution around the connected first hole and the third hole is different from the field intensity distribution around the connected second hole and the fourth hole. Based on the relationship

as well as

ΔE1 of the first lens is not equal to ΔE2 of the second lens. Therefore, F1 of the first lens and F2 of the second lens are not equal. Therefore, this embodiment adjusts the field by changing the spacing between the electrode layers. song.

In a possible implementation manner of the first aspect, the first part of the second electrode layer and the second part of the second electrode layer are in a first plane, and the first plane is perpendicular to the stacking direction.

Since the first part of the first electrode layer of the first electrode layer protrudes in a direction away from the second electrode layer relative to the second part of the first electrode layer, in this case, even if the first part of the second electrode layer of the second electrode layer is in contact with the second electrode The second part of the layer is in the same plane, and the distance between the first part of the first electrode layer and the first part of the second electrode layer is greater than the distance between the second part of the first electrode layer and the second part of the second electrode layer, so that the first part of the first electrode layer and the second part of the second electrode layer are in the same plane. ΔE1 of one lens is not equal to ΔE2 of the second lens. Furthermore, F1 of the first lens and F2 of the second lens are not equal. Therefore, this embodiment adjusts the field curvature by changing the spacing between the electrode layers. .

In a possible implementation manner of the first aspect, the diameter of the first hole is not equal to the diameter of the second hole.

It can be understood that when the aperture of the first hole and the aperture of the second hole are not equal, the larger the aperture, the smaller the field strength difference on both sides of the hole, the weaker the ability to converge the charged particle beam, and the farther the focus point is.

When the aperture of the first hole and the aperture of the second hole are not equal to each other in the following embodiments, for example, it is applied by adjusting the spacing between the first electrode layer and the second electrode layer (ie, adjusting the field intensity distribution). During field curvature correction, the distance between the first part of the first electrode layer and the first part of the second electrode layer may appear to be very large, which in turn will make the size of the entire electrostatic lens very large. In this case, the distance between the first part of the first electrode layer and the first part of the second electrode layer may become very large. The aperture scheme is used to adjust the field curvature by adjusting the field intensity distribution.

In a possible implementation manner of the first aspect, the aperture of the first hole is equal to the aperture of the third hole; and/or the aperture of the second hole is equal to the aperture of the fourth hole.

In a possible implementation of the first aspect, any part of the first part of the first electrode layer and the second part of the first electrode layer is a planar structure perpendicular to the stacking direction, and the first part of the first electrode layer and the second part of the first electrode layer There are steps at the junction of the sections.

It can be understood that the first part of the first electrode layer where the first hole is located and the second part of the first electrode layer where the second hole is located are planar structures perpendicular to the stacking direction. If the first part of the first electrode layer used to carry the first hole is If the first part of the electrode layer and the second part of the first electrode layer carrying the second hole are not in a planar structure, the electric field around the first hole is asymmetric, and the electric field around the second hole is also asymmetric, and the charged particles When passing through a hole with an asymmetric electric field, the trajectory will shift, and the preset focusing effect will not be achieved.

In a possible implementation of the first aspect, the electrostatic lens further includes: a first power terminal and a second power terminal, the first power terminal is electrically connected to the first electrode layer; the second power terminal is electrically connected to the second electrode layer.

In this case, when a voltage is applied to the first electrode layer, the voltages of the first part of the first electrode layer and the second part of the first electrode layer are equal. Similarly, when a voltage is applied to the second electrode layer , the voltages of the first part of the second electrode layer and the second part of the second electrode layer are equal. Compared with providing a power terminal for each part, the embodiment given in this application is easier to control.

In a possible implementation of the first aspect, the electrostatic lens further includes a dielectric layer, wherein the first electrode layer, the dielectric layer and the second electrode layer are stacked sequentially along the stacking direction; the dielectric layer is provided with a hole connecting the first hole and the third hole. hole, and a hole connecting the second hole and the fourth hole.

That is to say, by embedding the dielectric layer, the insulation between the first electrode layer and the second electrode layer is achieved.

In a second aspect, the present application provides a multi-beam charged particle system. The electrostatic lens includes a particle source and the electrostatic lens provided in any implementation of the first aspect. The electrostatic lens is arranged in the beam path of the charged particles.

The multi-beam charged particle system provided by the embodiment of the present application includes the electrostatic lens of the embodiment of the first aspect. Therefore, the multi-beam charged particle system provided by the embodiment of the present application and the electrostatic lens of the above technical solution can solve the same technical problems and achieve the same goal. The expected effects will not be described in detail here.

In a possible implementation of the second aspect, the multi-beam charged particle system is a multi-beam charged particle inspection system, such as a scanning electron microscope. In addition to the above-mentioned electrostatic lens and particle source, the multi-beam charged particle inspection system also includes : A stage used to install the object to be inspected, and a detector, in which the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be inspected; the detector is used to detect the secondary particles generated by the multi-beam charged particles from the object to be inspected. charged particles to produce a signal corresponding to the secondary charged particles.

For example, the above-mentioned electrostatic lens is used in a scanning electron microscope. In this case, the charged particle beam focused by the electrostatic lens will converge on the object to be inspected mounted on the stage, such as the wafer to be inspected. , compared with the existing multi-beam charged particle system, it can respond to defects on the object to be inspected more comprehensively and faster.

In a possible implementation of the second aspect, the multi-beam charged particle system is a multi-beam charged particle mapping system, such as an electron beam exposure machine. In addition to the above-mentioned electrostatic lens and particle source, the multi-beam charged particle inspection system also includes It includes: a stage for installing the object to be carved, and the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be carved coated with the anti-corrosion agent to form a particle beam spot on the object to be carved.

For example, the above-mentioned electrostatic lens is used in an electron beam exposure machine. In this case, the charged particle beams focused by the electrostatic lens will converge on the object to be engraved installed on the table. Compared with the existing multi-beam charged The particle system can improve the efficiency of engraving and shorten the engraving time.

In a third aspect, the present application improves a method for performing multi-beam charged particle inspection on a substrate. The method includes: using a particle source to generate charged particles; using an electrostatic lens arranged in the beam path of the charged particles to charge the multi-beam The particles are focused on the substrate; secondary charged particles generated from multiple beams of charged particles from the substrate are detected to generate signals corresponding to the secondary charged particles. The electrostatic lens here can be the electrostatic lens provided in any embodiment of the first aspect.

The method provided by the embodiments of the present application for multi-beam charged particle inspection of a substrate includes the electrostatic lens of the first embodiment. Therefore, the method provided by the embodiments of the present application and the electrostatic lens of the above technical solution can solve the same technical problem. and achieve the same expected effect, which will not be described again here.

In a possible implementation of the third aspect, when the electrostatic lens further includes: a first power terminal electrically connected to the first electrode layer, and a second power terminal electrically connected to the second electrode layer, when using charged particles arranged on The electrostatic lens in the beam path focuses the multi-beam charged particles on the substrate, which further includes: loading the first electrode layer with a first voltage through the first power supply terminal; loading the second electrode layer with a voltage different from the first voltage through the second power supply terminal. equal second voltage.

That is to say, voltage can be applied to the first electrode layer and the second electrode layer of the first lens, the second lens and other lenses in the electrostatic lens at the same time.

In a possible implementation manner of the third aspect, the diameter of the first hole is not equal to the diameter of the second hole.

In this case, the electric field intensity distribution when the first charged particle beam in the multi-part beam of charged particles passes through the connected first hole and the third hole is the same as when the second charged particle beam in the multi-part beam of charged particles passes through the connected The electric field intensity distributions at the second hole and the fourth hole are different.

In a possible implementation of the third aspect, the first part of the second electrode layer protrudes in a direction closer to the first electrode layer relative to the second part of the second electrode layer, and along the stacking direction, the port of the first hole is close to the third hole, The distance between the port of the third hole close to the first hole is d1, the distance between the port of the second hole close to the fourth hole, and the port of the fourth hole close to the second hole is d2, and d1= d2.

The electric field intensity distribution when the first charged particle beam in the multi-part beam of charged particles passes through the connected first hole and the third hole, and when the second charged particle beam in the multi-part beam of charged particles passes through the connected second hole The electric field intensity distribution is the same as that of the fourth hole.

In a possible implementation manner of the third aspect, the first part of the second electrode layer protrudes in a direction away from the first electrode layer relative to the second part of the second electrode layer.

In this way, the electric field intensity distribution when the first charged particle beam in the multi-part beam of charged particles passes through the connected first hole and the third hole is the same as when the second charged particle beam in the multi-part beam of charged particles passes through the connected third hole. The electric field intensity distributions at the second hole and the fourth hole are different.

In a possible implementation manner of the third aspect, the first part of the second electrode layer and the second part of the second electrode layer are in a first plane, and the first plane is perpendicular to the stacking direction.

Similarly, the electric field intensity distribution when the first charged particle beam in the multi-part beam of charged particles passes through the connected first hole and the third hole is the same as when the second charged particle beam in the multi-part beam of charged particles passes through the connected The electric field intensity distributions at the second hole and the fourth hole are different.

In a fourth aspect, the present application improves a method for engraving on an object coated with an anti-corrosion agent. The method includes: using a particle source to generate charged particles; and using static electricity arranged in the beam path of the charged particles. The lens focuses the multi-beam charged particles on the object to be engraved coated with the anti-corrosion agent to form a particle beam spot on the object to be engraved. The electrostatic lens here can be the electrostatic lens provided in any embodiment of the first aspect.

The method for engraving on an object coated with an anti-corrosion agent provided by the embodiments of the present application includes the electrostatic lens of the embodiment of the first aspect. Therefore, the method provided by the embodiment of the present application and the electrostatic lens of the above technical solution can solve the same problem. Technical issues and achieve the same expected effect will not be described again here.

In a possible implementation of the fourth aspect, when the electrostatic lens further includes: a first power terminal electrically connected to the first electrode layer, and a second power terminal electrically connected to the second electrode layer, when using charged particles arranged on The electrostatic lens in the beam path focuses the multi-beam charged particles on the object to be carved, which also includes: loading the first electrode layer with a first voltage through the first power terminal; loading the second electrode layer with the second voltage through the second power terminal. a second voltage that is not equal to the voltage.

In a possible implementation manner of the fourth aspect, the diameter of the first hole is not equal to the diameter of the second hole.

In a possible implementation of the fourth aspect, the first part of the second electrode layer protrudes relative to the second part of the second electrode layer in a direction closer to the first electrode layer, and along the stacking direction, the port of the first hole is close to the third hole, The distance between the port of the third hole close to the first hole is d1, the distance between the port of the second hole close to the fourth hole, and the port of the fourth hole close to the second hole is d2, and d1= d2.

In a possible implementation manner of the fourth aspect, the first part of the second electrode layer protrudes in a direction away from the first electrode layer relative to the second part of the second electrode layer.

In a possible implementation of the fourth aspect, the first part of the second electrode layer and the second part of the second electrode layer are in a first plane, and the first plane is perpendicular to the stacking direction.

In a fifth aspect, the present application provides an electrostatic lens, which includes: a first electrode layer, a second electrode layer, a first power terminal, a second power terminal, a third power terminal and a fourth power terminal; wherein, The first electrode layer and the second electrode layer are stacked, and the first electrode layer and the second electrode layer are insulated; the first electrode layer includes a first part of the first electrode layer and a second part of the first electrode layer, and the first electrode layer One part is insulated from the second part of the first electrode layer. The second electrode layer includes a first part of the second electrode layer and a second part of the second electrode layer. The first part of the second electrode layer is insulated from the second part of the second electrode layer. ; The first part of the first electrode layer and the first part of the second electrode layer are arranged along the stacking direction, and the second part of the first electrode layer and the second part of the second electrode layer are arranged along the stacking direction; the first part of the first electrode layer has a a first hole penetrating through the first electrode layer in the stacking direction; a second hole penetrating the first electrode layer in the stacking direction; and a first hole connected to the first hole formed in the first part of the second electrode layer. There is a third hole through the second electrode layer, and a fourth hole connected to the second hole is opened in the second part of the second electrode layer; the first power terminal is electrically connected to the first part of the first electrode layer; the second power terminal is connected to the first electrode layer The second part is electrically connected; the third power terminal is electrically connected to the first part of the second electrode layer; the fourth power terminal is electrically connected to the second part of the second electrode layer.

In the electrostatic lens provided by the embodiment of the present application, the first electrode layer is divided into an insulated and isolated first part of the first electrode layer and a second part of the first electrode layer, and the second electrode layer is divided into an insulated and isolated first part of the second electrode layer. and the second part of the second electrode layer, that is to say, the first part of the first electrode layer, the second part of the first electrode layer, the first part of the second electrode layer and the second part of the second electrode layer are independent structures. On the top, each part has a corresponding power terminal for providing voltage. Furthermore, the voltage value loaded on each part does not interfere with each other. The first part of the first electrode layer carrying the first hole and the third part carrying the third hole Field curvature correction of the first lens composed of the first part of the two electrode layers, and field curvature correction of the second lens composed of the second part of the first electrode layer carrying the second hole and the second part of the second electrode layer carrying the fourth hole independent of each other.

This embodiment can adjust the voltages of different parts to flexibly control the field curvature correction. The field curvature correction has higher flexibility and stronger applicability.

In a possible implementation of the fifth aspect, the first part of the first electrode layer and the second part of the first electrode layer are in the first plane, and the first part of the second electrode layer and the second part of the second electrode layer are in the second plane, And both the first plane and the second plane are perpendicular to the stacking direction.

In this case, the distance between the first part of the first electrode layer and the first part of the second electrode layer is equal to the distance between the second part of the first electrode layer and the second part of the second electrode layer. That is, the field intensity distributions of the first lens and the second lens are the same.

In a possible implementation manner of the fifth aspect, the diameter of the first hole is not equal to the diameter of the second hole.

When the unequal aperture of the first hole and the aperture of the second hole work together with the above-mentioned adjustment of the field intensity by adjusting the voltage, the field curvature is corrected.

In a possible implementation manner of the fifth aspect, the aperture of the first hole is equal to the aperture of the third hole; and/or the aperture of the second hole is equal to the aperture of the fourth hole.

In a possible implementation of the fifth aspect, the electrostatic lens further includes a third electrode layer and a fourth electrode layer. The first electrode layer, the second electrode layer, the third electrode layer and the fourth electrode layer are stacked in sequence. The third electrode layer The layer includes a first part of the third electrode layer and a second part of the third electrode layer. The first part of the third electrode layer is provided with a fifth hole connected to the third hole, and the second part of the third electrode layer is provided with a fourth hole connected to it. The fourth electrode layer includes a first part of the fourth electrode layer and a second part of the fourth electrode layer. The first part of the fourth electrode layer is provided with a seventh hole connected with the fifth hole. The fourth electrode layer The two parts are provided with an eighth hole connected by the sixth hole. Also, the first part of the third electrode layer is electrically connected to the fifth power terminal, the second part of the third electrode layer is electrically connected to the sixth power terminal, the first part of the fourth electrode layer is electrically connected to the seventh power terminal, and the fourth electrode layer The second part is electrically connected to the eighth power terminal.

When stacked first electrode layer, second electrode layer, third electrode layer and fourth electrode layer are used, voltages can be applied to different parts of different electrode layers to achieve correction of field curvature by adjusting the object distance.

In a possible implementation of the fifth aspect, the electrostatic lens further includes: a first dielectric layer and a second dielectric layer, and the first electrode layer, the first dielectric layer and the second electrode layer are stacked sequentially along the stacking direction; the first dielectric layer has an opening There is a hole connecting the first hole and the third hole, and a hole connecting the second hole and the fourth hole; between the first part of the first electrode layer and the second part of the first electrode layer, between the first part of the second electrode layer and the second The second parts of the electrode layer are separated by a second dielectric layer.

That is to say, by embedding the first dielectric layer and the second dielectric layer, the insulation between the first electrode layer and the second electrode layer, and the insulation between the first part of the first electrode layer and the second part of the first electrode layer are achieved. , and insulation between the first part of the second electrode layer and the second part of the second electrode layer.

In a sixth aspect, the present application provides a multi-beam charged particle system. The electrostatic lens includes a particle source and the electrostatic lens provided in any implementation of the fifth aspect. The electrostatic lens is arranged in the beam path of the charged particles.

The multi-beam charged particle system provided by the embodiment of the present application includes the electrostatic lens of the embodiment of the fifth aspect. Therefore, the multi-beam charged particle system provided by the embodiment of the present application and the electrostatic lens of the above technical solution can solve the same technical problems and achieve the same goal. The expected effects will not be described in detail here.

In a possible implementation of the sixth aspect, the multi-beam charged particle system is a multi-beam charged particle inspection system, such as a scanning electron microscope. In addition to the above-mentioned electrostatic lens and particle source, the multi-beam charged particle inspection system also includes : A stage used to install the object to be inspected, and a detector, in which the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be inspected; the detector is used to detect the secondary particles generated by the multi-beam charged particles from the object to be inspected. charged particles to produce a signal corresponding to the secondary charged particles.

For example, the above-mentioned electrostatic lens is used in a scanning electron microscope. In this case, by applying different voltages to different areas of different electrode layers, the charged particle beams focused by the electrostatic lens will converge on the object to be inspected mounted on the stage. On the object, for example, it is concentrated on the wafer to be inspected. Compared with the existing multi-beam charged particle system, it can respond to defects on the object to be inspected more comprehensively and faster.

In a possible implementation of the sixth aspect, the multi-beam charged particle system is a multi-beam charged particle mapping system, such as an electron beam exposure machine. In addition to the above-mentioned electrostatic lens and particle source, the multi-beam charged particle inspection system also includes It includes: a stage for installing the object to be carved, and the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be carved coated with the anti-corrosion agent to form a particle beam spot on the object to be carved.

For example, the above-mentioned electrostatic lens is used in an electron beam exposure machine. In this case, by loading different voltages on different areas of different electrode layers, the charged particle beams focused by the electrostatic lens will converge on the stand-by device installed on the table. When engraving objects, compared with the existing multi-beam charged particle system, the engraving efficiency can be improved and the engraving time can be shortened.

In the seventh aspect, the present application improves a method for performing multi-beam charged particle inspection on a substrate. The method includes: using a particle source to generate charged particles; and using an electrostatic lens arranged in the beam path of the charged particles to charge the multi-beams. The particles are focused on the substrate; secondary charged particles generated from multiple beams of charged particles from the substrate are detected to generate signals corresponding to the secondary charged particles. The electrostatic lens here can be the electrostatic lens provided in any embodiment of the fifth aspect.

The method provided by the embodiments of the present application for multi-beam charged particle inspection of a substrate includes the electrostatic lens of the embodiment of the fifth aspect. Therefore, the method provided by the embodiments of the present application and the electrostatic lens of the above technical solution can solve the same technical problem. and achieve the same desired effect.

In a possible implementation manner of the seventh aspect, the diameter of the first hole is not equal to the diameter of the second hole.

In an eighth aspect, the present application provides a method for engraving on an object coated with an anti-corrosion agent. The method includes: using a particle source to generate charged particles; and using static electricity arranged in the beam path of the charged particles. The lens focuses the multi-beam charged particles on the object to be engraved coated with the anti-corrosion agent to form a particle beam spot on the object to be engraved. The electrostatic lens here can be the electrostatic lens provided in any embodiment of the fifth aspect.

The method for engraving on an object coated with an anti-corrosion agent provided by the embodiments of the present application includes the electrostatic lens of the embodiment of the fifth aspect. Therefore, the method provided by the embodiment of the present application and the electrostatic lens of the above technical solution can solve the same problem. technical issues and achieve the same desired effect.

In a possible implementation manner of the eighth aspect, the diameter of the first hole is not equal to the diameter of the second hole.

In a ninth aspect, the present application provides an electrostatic lens, which includes: a first electrode layer, a second electrode layer, a stack of the first electrode layer and the second electrode layer, and between the first electrode layer and the second electrode layer insulation; the first electrode layer includes a first part of the first electrode layer and a second part of the first electrode layer; the second electrode layer includes a first part of the second electrode layer and a second part of the second electrode layer; the first part of the first electrode layer and The first part of the second electrode layer is arranged along the stacking direction, the second part of the first electrode layer and the second part of the second electrode layer are arranged along the stacking direction; there is a hole in the first part of the first electrode layer that penetrates the first electrode layer along the stacking direction. a first hole, a second hole penetrating the first electrode layer along the stacking direction is opened in the second part of the first electrode layer; a third hole connected to the first hole is opened in the first part of the second electrode layer, and the second hole is opened in the second part of the first electrode layer and passes through the first electrode layer in the stacking direction. A fourth hole connected to the second hole is opened in the second part of the electrode layer; wherein the diameter of the first hole is not equal to the diameter of the second hole.

In the electrostatic lens provided by the embodiment of the present application, since the apertures of the first hole and the second hole are not equal, the larger the aperture, the smaller the field strength difference on both sides of the hole, and the weaker the ability to converge the charged particle beam. , the farther the focus point is, the field curvature can be adjusted to achieve the purpose of flattening the focusing surface formed by the multi-beam charged particle system.

In a possible implementation manner of the ninth aspect, the aperture of the first hole is equal to the aperture of the third hole; and/or the aperture of the second hole is equal to the aperture of the fourth hole.

In a possible implementation of the ninth aspect, the first part of the first electrode layer and the second part of the first electrode layer are in the first plane, and the first part of the second electrode layer and the second part of the second electrode layer are in the second plane, And both the first plane and the second plane are perpendicular to the stacking direction.

In a possible implementation of the ninth aspect, the electrostatic lens further includes a dielectric layer, the first electrode layer, the dielectric layer and the second electrode layer are stacked in sequence along the stacking direction; the dielectric layer is provided with a hole connecting the first hole and the third hole, and a hole connecting the second hole and the fourth hole.

That is, by embedding the dielectric layer, the insulation between the first electrode layer and the second electrode layer is achieved.

In a possible implementation manner of the ninth aspect, the electrostatic lens further includes: a first power terminal and a second power terminal, the first power terminal is electrically connected to the first electrode layer; the second power terminal is electrically connected to the second electrode layer.

In a tenth aspect, the present application provides a multi-beam charged particle system. The electrostatic lens includes a particle source and the electrostatic lens provided in any implementation of the ninth aspect. The electrostatic lens is arranged in the beam path of the charged particles.

The multi-beam charged particle system provided by the embodiment of the present application includes the electrostatic lens of the embodiment of the ninth aspect. Therefore, the multi-beam charged particle system provided by the embodiment of the present application and the electrostatic lens of the above technical solution can solve the same technical problems and achieve the same goal. The expected effects will not be described in detail here.

In a possible implementation of the tenth aspect, the multi-beam charged particle system is a multi-beam charged particle inspection system, such as a scanning electron microscope. In addition to the above-mentioned electrostatic lens and particle source, the multi-beam charged particle inspection system also includes : A stage used to install the object to be inspected, and a detector, in which the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be inspected; the detector is used to detect the secondary particles generated by the multi-beam charged particles from the object to be inspected. charged particles to produce a signal corresponding to the secondary charged particles.

In a possible implementation of the tenth aspect, the multi-beam charged particle system is a multi-beam charged particle scribing system, such as an electron beam exposure machine. In addition to the above-mentioned electrostatic lens and particle source, the multi-beam charged particle inspection system also includes It includes: a stage for installing the object to be carved, and the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be carved coated with the anti-corrosion agent to form a particle beam spot on the object to be carved.

In an eleventh aspect, the present application improves a method for performing multi-beam charged particle inspection on a substrate. The method includes: using a particle source to generate charged particles; using an electrostatic lens arranged in the beam path of the charged particles to separate the multi-beam The charged particles are focused on the substrate; secondary charged particles generated from multiple beams of charged particles from the substrate are detected to generate signals corresponding to the secondary charged particles. The electrostatic lens here can be the electrostatic lens provided in any embodiment of the ninth aspect.

The method provided by the embodiments of the present application for multi-beam charged particle inspection of a substrate includes the electrostatic lens of the embodiment of the ninth aspect. Therefore, the method provided by the embodiments of the present application and the electrostatic lens of the above technical solution can solve the same technical problem. and achieve the same expected effect, which will not be described again here.

In a possible implementation manner of the eleventh aspect, when the electrostatic lens further includes: a first power terminal electrically connected to the first electrode layer, and a second power terminal electrically connected to the second electrode layer, when using the electrically charged The electrostatic lens in the beam path of the particles focuses the multi-beam charged particles on the object to be carved, which also includes: loading the first electrode layer with a first voltage through the first power terminal; loading the second electrode layer with the second power terminal. The first voltage is not equal to the second voltage.

In a twelfth aspect, the present application provides a method for engraving on an object coated with an anti-corrosion agent. The method includes: using a particle source to generate charged particles; and using an electrostatic lens arranged in the beam path of the charged particles. The multi-beam charged particles are focused on the object to be engraved coated with the anti-corrosion agent to form a particle beam spot on the object to be engraved. The electrostatic lens here can be the electrostatic lens provided in any embodiment of the ninth aspect.

The method for engraving on an object coated with an anti-corrosion agent provided by the embodiments of the present application includes the electrostatic lens of the embodiment of the ninth aspect. Therefore, the method provided by the embodiment of the present application and the electrostatic lens of the above technical solution can solve the same problem. technical issues and achieve the same desired effect.

In a possible implementation manner of the twelfth aspect, when the electrostatic lens further includes: a first power terminal electrically connected to the first electrode layer, and a second power terminal electrically connected to the second electrode layer, when using the electrically charged The electrostatic lens in the beam path of the particles focuses the multi-beam charged particles on the object to be carved, which also includes: loading the first electrode layer with a first voltage through the first power terminal; loading the second electrode layer with the second power terminal. The first voltage is not equal to the second voltage.

Description of the drawings

Figure 1 is a structural diagram of a multi-beam charged particle system in the prior art;

Figure 2 is used to illustrate the structure of the virtual source position of the multi-beam charged particle system in Figure 1;

Figure 3 is used to illustrate that the focusing surface of the multi-beam charged particle system in Figure 1 is a curved surface;

Figure 4 is a schematic structural diagram of a multi-beam charged particle system according to an embodiment of the present application;

Figures 5a and 5b are used to illustrate the focusing principle of the electrostatic lens;

Figures 6a and 6b are used to illustrate the Gaussian imaging theorem;

Figure 7 is a schematic structural diagram of an electrostatic lens according to an embodiment of the present application;

Figure 8 is an enlarged view of X in Figure 7;

Figure 9 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figures 10a and 10b are imaging comparison views of the electrostatic lens according to the embodiment of the present application and the existing electrostatic lens;

Figures 11a and 11b are imaging comparison views of the electrostatic lens according to the embodiment of the present application and the existing electrostatic lens;

Figures 12a and 12b are imaging comparison diagrams of the electrostatic lens according to the embodiment of the present application and the existing electrostatic lens;

Figures 13a and 13b are partial structural schematic diagrams of the electrostatic lens according to the embodiment of the present application;

Figure 14 is a schematic structural diagram of an electrostatic lens according to an embodiment of the present application;

Figure 15 is a schematic diagram of the focusing principle of Figure 14;

Figure 16a and Figure 16b are schematic structural diagrams of the electrostatic lens according to the embodiment of the present application;

Figures 17a and 17b are schematic structural diagrams of the electrostatic lens according to the embodiment of the present application;

Figures 18a, 18b and 18c are partial structural schematic diagrams of the electrostatic lens according to the embodiment of the present application;

Figure 19 is a schematic structural diagram of a multi-beam charged particle system according to an embodiment of the present application;

Figure 20 is a schematic structural diagram of a multi-beam charged particle system according to an embodiment of the present application;

Figure 21 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 22 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 23 is a schematic structural diagram of a multi-beam charged particle system according to an embodiment of the present application;

Figure 24 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 25 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 26 is a schematic structural diagram of a multi-beam charged particle system according to an embodiment of the present application;

Figure 27 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 28a, Figure 28b and Figure 28c are partial structural schematic diagrams of the electrostatic lens according to the embodiment of the present application;

Figure 29 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 30 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 31 is the M-direction view of Figure 30;

Figure 32 is an N-direction view of Figure 30;

Figure 33 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 34 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 35 is a partial structural schematic diagram of an electrostatic lens according to an embodiment of the present application;

Figure 36 is a schematic structural diagram of an electrostatic lens according to an embodiment of the present application;

Figure 37 is a schematic structural diagram of an electrostatic lens according to an embodiment of the present application;

Figure 38 is a schematic structural diagram of a multi-beam charged particle system according to an embodiment of the present application;

Figure 39 is a schematic structural diagram of a multi-beam charged particle system according to an embodiment of the present application;

Figure 40 is a schematic structural diagram of a multi-beam charged particle system according to an embodiment of the present application;

Figure 41 is a schematic structural diagram of a multi-beam charged particle system according to an embodiment of the present application;

Figure 42 is a schematic structural diagram of a particle optical scribing system according to an embodiment of the present application;

Figure 43 is a schematic structural diagram of a particle optical inspection system according to an embodiment of the present application.

Reference signs:

1-particle source; 2-collimator; 201-electrode layer; 202-hole; 3-beam splitter; 4-first focusing mirror; 5-second focusing mirror; 6-biaser; 7-object; 8-detector; 9-station; 100-electrostatic lens; 101-first electrostatic lens; 102-second electrostatic lens; 11, 101-first electrode layer; 12, 102-second electrode layer; 21, 201- The first hole; 22, 202-the second hole; 203-the third hole; 204-the fourth hole; 3-dielectric layer; A1-the first part of the first electrode layer; A2-the second part of the first electrode layer; B1- The first part of the second electrode layer; B2-the second part of the second electrode layer.

Detailed ways

Embodiments of the present application provide a multi-beam charged particle system. The multi-beam charged particle system can be used for microscopic imaging. For example, it can be applied in a scanning electron microscope (scanning electron microscope, SEM). In SEM, in addition to including multi-beam In addition to the beam charged particle system, it can also include detection elements, such as detectors. Such SEM can be used to inspect objects. For example, it can inspect semiconductor wafers (wafers) for process defects. The specific inspection process can be: multi-beam The electron beam generated by the charged particle system is focused on the wafer to form an electron beam spot on the wafer. The detector collects the secondary electrons and backscattered electrons generated on the wafer surface, and can obtain the morphology information and atomic number of the wafer surface. Characterization information, etc., obtaining the morphology information and atomic number characterization information of the wafer surface is based on the different secondary electron yields of materials with different atomic numbers. The electron reflection angles and quantities of different surface shapes are different, and the reflection on the image is bright. Different areas with distinct darkness, and further, electronic image information can be used to determine whether there are defects on the wafer surface, whether the etching pattern is complete, etc.

In addition, multi-beam charged particle systems can also be used in electron beam exposure machines. For example, when manufacturing semiconductor devices and integrated circuits, it is necessary to form the required patterns on wafers. These patterns can be obtained by exposure and development using electron beam exposure machines. .

In the above-mentioned multi-beam charged particle system, other types of charged particles can also be used instead of electrons, for example, they can be ions (such as helium ions), positrons or myons.

Figure 4 shows a structural diagram of a multi-beam charged particle system. The multi-beam charged particle system may include a particle source 1. The particle source 1 is a particle generator structure that can generate charged particles. The specific charged particles are The type can refer to the above-mentioned charged particle types. A particle source is shown in Figure 4. The multi-beam charged particle system formed in this way can be called a single charged-particle source. A multi-beam charged particle system .

In a single charged-particle source multi-beam charged particle system, the multi-beam charged particle system also includes a collimator (collimator) 2 and a beam splitter (aperture array) 3 shown in Figure 4. The beam splitter 2 and the beam splitter 3 are arranged sequentially along the beam path of the charged particles generated by the particle source 1. Among them, the collimator 2 has beam expansion and collimation functions, and the beam splitter 3 can divide the charged particle beam expanded and collimated by the collimator 2 into multiple charged particle beams.

In some alternative embodiments, as shown in Figure 4, the collimator 2 can be an electronic lens structure, that is, the collimator 2 is formed by stacking at least two electrode layers 201, and the stacked multi-layer electrode layers 201 A hole 202 with a larger diameter is opened in the upper part. Different voltages are applied to the adjacent electrode layers 201 stacked up and down to form an electric field. In this way, when the charged particle beam generated by the particle source 1 passes through the hole 201, Beam expansion and collimation functions can be achieved. For example, in conjunction with Figure 4, the middle electrode layer 201 in the collimator is loaded with a higher voltage than the other electrode layers, and then there will be a divergence near the middle electrode layer 201. In the electric field area, when electrons pass through the divergent electric field area, they will be subject to an electric field force from the center to the edge, so that the electron beam changes outward to achieve the beam expansion function; the loading ratio of the bottom electrode layer 201 in the collimator is The voltage of the electrode layer 201 in the middle is low, and there will be a concentrated electric field area near the bottom electrode layer 201. When the electrons pass through the concentrated electric field area, they will experience an electric field force directed from the edge to the center, so that the electron beam There is a change that converges toward the center to achieve the collimation function.

In the collimator 2, since the diameter of the hole 201 penetrating the electrode layer 202 is relatively large, as shown in Figure 4, in the collimator 2, at different positions from the central axis L, the charged particle beam The acting forces are different. In this way, a field curvature phenomenon will occur. If the field curvature is not corrected, the focusing plane of the focusing point of the multiple charged particle beams passing through the beam splitter 3 is For the curved surface structure shown in Figure 3, whether the multi-beam charged particle system is applied to microscopic imaging, electronic etching, or mask repair, the focusing surface of the curved surface will affect the resolution. For example, the resulting focusing surface will be a curved surface. When the multi-beam charged particle system is used for defect detection in semiconductor wafer processes, it cannot clearly reflect the defect characteristics, thereby reducing the detection effect. Therefore, flattening the focus surface into a planar focus surface as shown in Figure 4 is the goal of this field. It can also be understood in conjunction with Figure 3 that the distance between the focus point and the target point is the defocus distance (defocus). When the defocus correction of a focus point is zero, the focus surface can be flattened into a plane.

In order to eliminate the defocus of the focusing point and flatten the focusing surface into a plane, as shown in Figure 4, the present application provides an electrostatic lens 100. As a focusing lens, the electrostatic lens 100 can be disposed through beam splitting. On the beam path of the charged particle beam behind the device 3, the electrostatic lens 100 can correct the defocus on the basis of achieving focusing to achieve the purpose of making the focusing surface a flat surface.

The electrostatic lens 100 involved in the present application will be described in detail below with reference to the accompanying drawings.

Before describing the achievable structure of the electrostatic lens 100, the focusing principle of the electrostatic lens will be explained with reference to FIG. 5a and FIG. 5b.

Combining Figure 5a and Figure 5b, Figure 5a is a partial structural diagram of a top view of an electrostatic lens. Figure 5b is a cross-sectional view of A-A in Figure 5a. It can be seen from Figure 5b that the electrostatic lens mainly includes a first electrode layer 11 and The second electrode layer 12, where the first electrode layer 11 and the second electrode layer 12 are both made of conductive materials, for example, can be made of metal, and the first electrode layer 11 and the second electrode layer 12 are insulated, The first electrode layer 11 has a hole 21 , and the second electrode layer 12 has a hole 22 penetrating the hole 21 .

It should be noted that this application does not limit the edge shape of the electrostatic lens, and is not limited to the shape shown in Figure 5a. In addition, there is no special arrangement for the multiple holes in the electrostatic lens used to pass through the charged particle beam. Limitation: Figure 5a is only an exemplary illustration and is not limited to the arrangement shown in Figure 5a.

As shown in Figure 5b, the focusing principle of the electrostatic lens is: when a first voltage V1 is applied to the first electrode layer 11, and a second voltage V2 that is not equal to the first voltage V1 is applied to the second electrode layer 12, an electric field E will be formed. . For example, in Figure 5b, a voltage of 10kV is exemplarily applied to the first electrode layer 11, and a voltage of 3kV is applied to the second electrode layer 12. Figure 5b shows the electric field line E, and the equipotential line (as the dotted line in Figure 5b (shown in Figure 5b), there is a uniform electric field between the first electrode layer 11 and the second electrode layer 12 and close to the center area (a straight dotted line in Figure 5b). However, near the hole 21 and the hole 22, there is a uniform electric field. Non-uniform electric field (the curved dotted line in Figure 5b), assuming that electrons move from the upstream of the first electrode layer 11 towards the first electrode layer 11 to A, they will experience the electric field force F in the direction shown in the figure. , the electric field force F can be decomposed into perpendicular F1 and F2. Under the action of the electric field force F1, the electron beam can be converged and the focusing function can be achieved.

Figure 6a and Figure 6b embody the Gaussian imaging theorem.

The structural diagram of the electrostatic lens 100 can be formed based on the mechanism shown in Figures 6a and 6b, where f is the focal length, U is the object distance, V is the image distance, and the focal length f of the first lens shown in Figure 6a and Figure 6 When the focal length f of the second lens shown in 6b is equal, the image distance V can be changed by adjusting the object distance U of the lens. Combining Figures 6a and 6b, when the object distance increases by ΔU from U in Figure 6a, it becomes as shown in Figure 6a When U+ΔU in 6b, the image distance will change from V in Figure 6a to V-ΔV in Figure 6b. Therefore, the change amount of the focus point is ΔU-ΔV. According to the inconsistency between the object distance and the distance change rate, The focus point position of the charged particle beam can be adjusted, and the focus point position changes from F1 in Figure 6a to F2 in Figure 6b.

Figure 7 is based on the above Gaussian imaging theorem.

A structural diagram of an electrostatic lens 100 is formed. Figure 8 is an enlarged view of X in Figure 7. Combining Figures 7 and 8, the electrostatic lens 100 includes a stacked first electrode layer 101 and a second electrode layer 102. And the first electrode layer 101 and the second electrode layer 102 are separated by the dielectric layer 3 to achieve insulation between the two electrode layers, thereby preventing the first electrode layer 101 and the second electrode layer 102 from being electrically connected.

Continuing with FIG. 7 and FIG. 8 , the first electrode layer 101 includes a first part A1 of the first electrode layer and a second part A2 of the first electrode layer. The first part A1 of the first electrode layer has a first hole penetrating through the first electrode layer 101 . 201. The second part A2 of the first electrode layer has a second hole 202 penetrating through the first electrode layer 101.

7 and 8, the second electrode layer 102 includes a first part B1 of the second electrode layer and a second part B2 of the second electrode layer. The first part B1 of the second electrode layer has a third hole penetrating the second electrode layer 102. 203. The second part B2 of the second electrode layer has a fourth hole 204 penetrating through the second electrode layer 102.

Continuing to combine Figures 7 and 8, the first part A1 of the first electrode layer and the first part B1 of the second electrode layer are arranged up and down along the stacking direction P, and the second part A2 of the first electrode layer and the second part B2 of the second electrode layer are also arranged. They are arranged up and down along the stacking direction P. In addition, the first hole 201 and the third hole 203 are connected, and the second hole 202 and the fourth hole 204 are connected.

It can be understood that, as shown in Figure 8, the electrostatic lens includes a first lens and a second lens, where the first lens includes: a first part A1 of the first electrode layer carrying the first hole 201 and a second part A1 of the third hole 203. The first part B1 of the electrode layer; the second lens includes: a second part A2 of the first electrode layer carrying the second hole 202 and a second part B2 of the second electrode layer carrying the fourth hole 204 .

8, the first part A1 of the first electrode layer protrudes in a direction away from the second electrode layer 102 relative to the second part A2 of the first electrode layer, and the first part B1 of the second electrode layer is protruding relative to the second part A2 of the second electrode layer. The portion B2 protrudes toward the first electrode layer 101 .

In some embodiments, in conjunction with FIG. 9 , the distance d between the port of the first hole 201 close to the third hole 203 and the port of the third hole 203 close to the first hole 201 can be set to the distance d between the port of the second hole 202 close to the first hole 201 . The distance d between the port of the fourth hole 204 and the port of the fourth hole 204 close to the second hole 202 is equal. In this case, the focal length f1 of the first lens and the focal length f2 of the second lens are equal.

The following explains the protrusion of the first part A1 of the first electrode layer in a direction away from the second electrode layer 102 relative to the second part A2 of the first electrode layer: the first part A1 of the first electrode layer has two opposite surfaces. The surfaces may be defined as a first surface and a second surface. The second part A2 of the first electrode layer has two opposite surfaces. The two surfaces are defined as a third surface and a fourth surface. The first part A1 of the first electrode layer is opposite. The second part A2 of the first electrode layer protrudes in a direction away from the second electrode layer 102 , that is, there is a gap between the first surface and the third surface along the stacking direction P, and between the second surface and the fourth surface along the stacking direction P. Has spacing.

Since the focal length f1 of the first lens is equal to f2 of the second lens, and since the first lens is convex relative to the second lens, if the electrostatic lens 100 is applied in a multi-beam charged particle system, the first lens will be convex relative to the second lens. The lens is closer to the particle source. Compared with the existing first lens and second lens in the same plane structure, the object distance U1 of the first lens and the object distance U2 of the second lens are changed. According to Gaussian imaging theorem

The image distance V1 of the first lens and the image distance V2 of the first lens will be changed. In this case, the focus point F1 of the first lens and the focus point F2 of the second film hole lens will appear as shown in Figure 8 and Figure 9. Not in a straight line.

Figure 10a and Figure 10b provide a schematic diagram of the correction of an electrostatic lens, as shown in Figure 10a. When the existing uncorrected focusing surface is a concave surface, an electrostatic lens 100 including the structure shown in Figures 8 and 9 can be used. It can be seen from Figure 10b that the convex electrostatic lens 100 can perform reverse compensation on the focusing surface to be corrected, so that the focusing surface can be flattened into a plane.

The convex shape of the electrostatic lens needs to be determined according to the shape of the focusing surface to be corrected. Figures 11b and 12b show the convex shapes of two electrostatic lenses.

For example, as shown in Figure 11a, when the existing uncorrected focusing surface is a convex surface, the electrostatic lens 100 with the structure shown in Figure 11b can be used. That is, the concave electrostatic lens 100 shown in Figure 11b can be used to correct the focusing surface. Perform reverse compensation to flatten the focus surface.

For example, as shown in Figure 12a, when the existing uncorrected focusing surface is a wavy surface with convex and concave surfaces, the electrostatic lens 100 with the structure shown in Figure 12b can be used, that is, the electrostatic lens with the wavy surface shown in Figure 12b 100 can perform reverse compensation on the focus surface to be corrected to flatten the focus surface.

In the above-mentioned electrostatic lens 100 shown in FIG. 10b, FIG. 11b, and FIG. 12b, the electrostatic lens 100 includes three electrode layers. Of course, it may also be two electrode layers, or three or more electrode layers. When the number of electrode layers is greater, the controllable voltage is more and the adjustment is easier. When the voltage is the same, the defocus range that the electrostatic lens can be adjusted is larger and the applicability is better.

Figure 13a shows a structure in which the first part A1 of the first electrode layer protrudes relative to the second part A2 of the first electrode layer, and the first part B1 of the second electrode layer protrudes relative to the second part B2 of the second electrode layer, that is, The first part A1 of the first electrode layer and the second part A2 of the first electrode layer both have a planar structure perpendicular to the stacking direction P. Similarly, the first part B1 of the second electrode layer and the second part B2 of the second electrode layer also have a planar structure perpendicular to the stacking direction P. Planar structure vertical to direction P.

Figure 13b shows another structure in which the first part A1 of the first electrode layer protrudes relative to the second part A2 of the first electrode layer, and the first part B1 of the second electrode layer protrudes relative to the second part B2 of the second electrode layer, that is, , any part of the first part A1 of the first electrode layer, the second part A2 of the first electrode layer, the first part B1 of the second electrode layer, or the second part B2 of the second electrode layer is an inclined plane structure that is not perpendicular to the stacking direction P.

In other alternative embodiments, any part of the first part A1 of the first electrode layer, the second part A2 of the first electrode layer, the first part B1 of the second electrode layer, or the second part B2 of the second electrode layer is not plane, but Adopt curved structure. Of course, other protruding forms can also be used.

The protruding form shown in Figure 13a is compared with the protruding form shown in Figure 13b. Since the first part A1 of the first electrode layer and the second part A2 of the first electrode layer are both planar structures perpendicular to the stacking direction P, in this case, The electric field distribution around the connected first hole 201 and the third hole 203 is symmetrical about the central axis of the hole. In this way, the electric field force experienced by the charged particle beam passing through the first hole 201 and the third hole 203 is Symmetrical, furthermore, the movement trajectory of the charged particle beam as shown in Figure 13b will not deviate. Therefore, the protruding form shown in Figure 13a can further improve the imaging quality.

However, during the actual processing of the first part A1 of the first electrode layer, the second part A2 of the first electrode layer, the first part B1 of the second electrode layer, and the second part B2 of the second electrode layer, within the processing error range, it is basically guaranteed that each It suffices that the portion is a planar structure perpendicular to the stacking direction P.

Figure 14 is used to illustrate the principle diagram for forming another electrostatic lens, that is, the electrostatic lens 100 can also be formed based on the mechanism shown in Figure 14. In Figure 14, the first electrode layer 101 and the second electrode of the first lens The distance d between the layers 102 is equal to the distance d between the first electrode layer 101 and the second electrode layer 102 of the second lens. The difference between the first lens and the second lens is: the aperture S1 of the hole of the first lens, is larger than the aperture S2 of the hole of the second lens.

Figure 15 shows the imaging principle of the structure shown in Figure 14. In Figure 15, when the first electrode layer 101 is loaded with a first voltage, for example, a 10kV voltage is loaded, the second electrode layer 102 is loaded with a voltage different from the first voltage. The second voltage, for example, 5kV voltage is applied. Since the aperture size of the hole opened by the first lens and the hole opened by the second lens are different, furthermore, the field intensity distribution around the hole of the first lens, The field strength distribution around the hole of the second lens is different, and the larger the hole diameter, the smaller the field strength difference ΔE.

Based on relationships

Here F is the focusing distance, A is a constant, U _K is the kinetic energy of the charged particle beam when passing through the hole (in the same multi-beam charged particle system, U _K is a constant value), ΔE is the field strength difference, in the figure 15, since the aperture of the hole of the first lens is larger than the aperture of the hole of the second lens, and the ΔE1 of the first lens is smaller than the ΔE2 of the second lens, therefore, the F1 of the first lens is larger than the F2 of the second lens, so that It appears that the focusing point F1 of the first lens and the focusing point F2 of the second lens shown in Figure 15 are not on a straight line.

Figures 16a and 16b provide a structural diagram of an electrostatic lens 100 formed based on the mechanism shown in Figures 14 and 15 above. Figure 16b is a top view of Figure 16a. It can be seen from Figure 16b that the electrostatic lens formed on The diameters of the holes can be set to be unequal. As for whether the diameter of these holes gradually increases from the central area toward the edge area, or whether the hole diameter gradually decreases, it needs to be determined according to the defocus size to be corrected. Figures 16a and 16b only show an exemplary structure.

Figure 17a and Figure 17b show the structure of another electrostatic lens. Figure 17b is a top view of Figure 17a. The structure of the electrostatic lens 100 is based on the Gaussian imaging theorem shown in Figure 6a and Figure 6b.

It is formed by the imaging mechanism shown in Figures 14 and 15.

The electrostatic lens structure shown in Figures 17a and 17b includes three electrode layers. Each two electrode layers are separated by a dielectric layer, and these three electrode layers form a convex structure. In addition, as shown in Figures 17a and 17b Figure 17b, the holes formed in the electrostatic lens 100 are not completely equal.

The following is an analysis of the benefits of the structure shown in Figures 17a and 17b in conjunction with Figures 18a, 18b and 18c. In Figures 18a, 18b and 18c, the voltage V1 of the first electrode layer 101 in Figure 18a, and The voltage V1 of the first electrode layer 101 in Figure 18b and the voltage V1 of the first electrode layer 101 in Figure 18c are equal. Similarly, the voltage V2 of the second electrode layer 102 in Figure 18a is the same as the voltage V2 of the second electrode layer 102 in Figure 18b The voltage V2 of the second electrode layer 102 and the voltage V2 of the second electrode layer 102 in FIG. 18c are equal. In addition, the distance between the first electrode layer 101 and the second electrode layer 102 is both d.

Comparing Figure 18a and Figure 18b, when it is necessary to change the focus point F1 of the first lens in Figure 18a to the focus point F11 of the lens in Figure 18b, it is necessary to make the first lens more protruding from the second lens, and then It will appear that the thickness P1 of the electrostatic lens in (a) increases to P2 in Figure 18b, which will cause the size of the entire electrostatic lens along the stacking direction P to increase. However, if the structure shown in Figure 18c is adopted, that is, when the aperture of the hole of the first lens is reduced from the original S to S1, the focus point F1 of the first lens can also be adjusted to the focus point F11, as shown in Figure Comparing Figure 18b with Figure 18c, the size of the entire electrostatic lens along the stacking direction P remains unchanged and is still P1.

The benefits of the structures shown in Figures 18a, 18b and 18c can be analyzed from another angle. For example, when the position of the focus point is adjusted by forming holes of different apertures, if the defocus is larger, holes with larger apertures need to be opened. In this case, the number of holes per unit area of the electrostatic lens will be smaller. , As a result, the number of charged particle beams coming out of the electrostatic lens will be reduced. If this multi-beam charged particle system is used for the etching process, the etching time will be extended and the work efficiency will be reduced.

In order to avoid opening a small number of holes per unit area and to improve operating efficiency, the difference in aperture can be reduced, and the lens can be protruded to change the object distance and adjust the focus point position.

Figure 19 shows a structural diagram of a multi-beam charged particle system. In addition to the particle source 1, the collimator 2 and the beam splitter 3, the multi-beam charged particle system also includes an electrostatic lens 100. The multi-beam charged particle system formed can be called a multi-charged-particle beam or a multi-optical column multi-beam charged particle system.

In the multi-charged-particle beam multi-optical column multi-beam charged particle system shown in Figure 19, there is one electrostatic lens 100, thereby forming a multi-beam multi-column multi-beam charged particle system adjusted by a single focusing module, and, The electrostatic lens 100 here is based on the Gaussian imaging theorem shown in Figure 6a and Figure 6b.

It is formed by the imaging mechanism shown in Figures 14 and 15.

In some implementations, for example, in some cases where the defocus difference is small, a multi-charged-particle beam multi-optical column multi-beam charged particle system adjusted by a single focusing module shown in Figure 19 can be used to achieve a flat focus surface. change.

Figure 20 shows the structural diagram of another multi-charged-particle beam multi-optical column multi-beam charged particle system. In this multi-beam charged particle system, the electrostatic lens includes a first electrostatic lens 101 and a second electrostatic lens 102, so that , forming a multi-module adjusted multi charged-particle beam multi optical column multi-beam charged particle system. Each of the first electrostatic lens 101 and the second electrostatic lens 102 here is based on the Gaussian imaging theorem shown in Figure 6a and Figure 6b.

It is formed by the imaging mechanism shown in Figures 14 and 15.

In other embodiments, for example, for situations where the defocus difference is large, if the multi-charged-particle beam multi-optical column multi-beam charged particle system adjusted by a single focusing module shown in Figure 19 is used, the edge of the electrostatic lens will be caused. There is a large difference between the aperture of the hole in the area and the hole in the center area. Under the premise of fixing the aperture size in the edge area, it is necessary to reduce the aperture size in the center area. This will increase the difficulty of processing the electrostatic lens, and the adjustment ability is limited. . At this time, the multi-module-adjusted multi-charged-particle beam multi-optical column multi-beam charged particle system shown in Figure 20 can be used, which can share the adjustment pressure of each electrostatic lens and increase the adjustment flexibility.

Figure 21 is used to illustrate a schematic diagram for forming another electrostatic lens. That is, the electrostatic lens 100 can also be formed based on the mechanism shown in Figure 21. In Figure 21, the aperture S of the hole of the first lens is equal to the second lens. The aperture S of the hole, the difference between the first lens and the second lens is: the distance d1 between the first electrode layer 101 and the second electrode layer 102 of the first lens is larger than the distance d1 between the first electrode layer 101 and the second electrode layer 102 of the second lens. The distance d2 between the two electrode layers 102.

Based on relationships

as well as

Among them, F in the formula is the focusing distance, A is a constant, U _K is the kinetic energy of the charged particle beam when passing through the hole (in the same multi-beam charged particle system, U _K is a constant value), Δu is the two electrodes The voltage difference loaded on the layer, d is the distance between the two electrode layers. In Figure 21, when the voltage applied to the first electrode layer 101 of the first lens and the first electrode layer 101 of the second lens is the same, similarly, the second electrode layer 102 of the first lens and the second electrode layer 102 of the second lens The voltages loaded on the two electrode layers 102 are the same. Furthermore, Δu1 of the first lens is equal to Δu2 of the second lens. However, because d1 of the first lens is greater than d2 of the second lens, ΔE1 of the first lens, It is smaller than the ΔE2 of the second lens. Therefore, the F1 of the first lens can be obtained, which is larger than the F2 of the second lens. In this way, the focusing point F1 of the first lens and the focusing point F2 of the second lens shown in Figure 21 are not on a straight line.

Figure 22 shows the structure of an electrostatic lens. The structure of the electrostatic lens 100 is formed based on the above-mentioned imaging mechanism shown in Figure 21.

In FIG. 22 , the first part A1 of the first electrode layer protrudes in a direction away from the second electrode layer 102 relative to the second part A2 of the first electrode layer, and the first part B1 of the second electrode layer and the second part B2 of the second electrode layer are at In the same plane perpendicular to the stacking direction P, in this case, the distance d1 between the first part A1 of the first electrode layer and the first part B1 of the second electrode layer is the same as the distance d1 between the second part A2 of the first electrode layer and the second part A2 of the second electrode layer. The distance d2 between the two parts B2 is not equal.

Figure 23 shows the structural diagram of a multi-charged-particle beam multi-optical column multi-beam charged particle system. In this multi-beam charged particle system, in addition to particle source 1, collimator 2 and beam splitter 3 , an electrostatic lens 100 is also included. The electrostatic lens 100 here is formed based on the above-mentioned FIG. 22 .

Figure 24 shows the structure of an electrostatic lens. The structure of the electrostatic lens 100 is also formed based on the above-mentioned imaging mechanism shown in Figure 21.

In FIG. 24 , the first portion A1 of the first electrode layer protrudes in a direction away from the second electrode layer 102 relative to the second portion A2 of the first electrode layer. Similarly, the first portion B1 of the second electrode layer protrudes relative to the second portion A2 of the second electrode layer. The portion B2 protrudes toward the direction close to the first electrode layer 101, but the protruding degree of the first portion A1 of the first electrode layer and the second portion A2 of the first electrode layer are different, so that the first portion A1 of the first electrode layer and the second portion A2 of the first electrode layer protrude. The distance d1 between the first part B1 of the second electrode layer is not equal to the distance d2 between the second part A2 of the first electrode layer and the second part B2 of the second electrode layer.

Figure 25 shows the structure of an electrostatic lens. The structure of the electrostatic lens 100 is also formed based on the above-mentioned imaging mechanism shown in Figure 21.

In FIG. 25 , the first part A1 of the first electrode layer protrudes in a direction away from the second electrode layer 102 relative to the second part A2 of the first electrode layer, and the first part B1 of the second electrode layer faces towards the second part B2 of the second electrode layer. The distance d1 between the first part A1 of the first electrode layer and the first part B1 of the second electrode layer is equal to the distance d1 between the second part A2 of the first electrode layer and the second part B1 of the second electrode layer. The distance d2 between the two parts B2 is not equal.

Figure 26 shows the structural diagram of a multi-charged-particle beam multi-optical column multi-beam charged particle system. In this multi-beam charged particle system, in addition to particle source 1, collimator 2 and beam splitter 3 , an electrostatic lens 100 is also included. The electrostatic lens 100 here is formed based on the above-mentioned FIG. 25 .

In the above-mentioned electrostatic lenses shown in Figures 22, 24 and 25 and other electrostatic lenses, other electrostatic lenses can be formed by combining with the imaging mechanism (changing the aperture) shown in Figure 15. For example, Figure 27 is the one shown in Figure 27. 25, the aperture S1 of the first lens is set smaller than the aperture S2 of the second lens.

The benefits of the structure shown in Figure 27 will be analyzed below in conjunction with Figure 28a, Figure 28b and Figure 28c. In Figure 28a, Figure 28b and Figure 28c, the voltage V1 of the first electrode layer 101 in Figure 28a, and the voltage V1 in Figure 28b The voltage V1 of the first electrode layer 101 and the voltage V1 of the first electrode layer 101 in Figure 28c are equal. Similarly, the voltage V2 of the second electrode layer 102 in Figure 28a and the voltage V2 of the second electrode in Figure 28b The voltage V2 of the layer 102 and the voltage V2 of the second electrode layer 102 in FIG. 28c are equal. In addition, the distance between the first electrode layer 101 and the second electrode layer 102 is both d.

Comparing Figure 28a and Figure 28b, when it is necessary to change the focus point F1 of the first lens in Figure 28a to the focus point F11 of the lens in Figure 28b, it is necessary to change the first part of the first electrode layer in the first lens and The spacing between the second parts of the first electrode layer increases from d2 to d21, and then the thickness P1 of the electrostatic lens in Figure 28a increases to P2 in Figure 28b, which results in the thickness of the entire electrostatic lens along the stacking direction P. Increased size. However, if the structure shown in Figure 28c is adopted, that is, when the aperture of the hole of the first lens is reduced from the original S to S1, the focus point F1 of the first lens can be adjusted to the focus point F11, as shown in Figure 28a Compared with Figure 28c, the size of the entire electrostatic lens along the stacking direction P remains unchanged and is still P1.

In the above embodiment, as shown in Figure 27, any one of the first hole, the second hole, the third hole and the fourth hole is a straight hole. The straight hole can also be explained in this way, along the axial direction of the hole, If the diameter of the hole remains unchanged, it can be called a straight hole. In some other embodiments, as shown in Figure 29, any one of the first hole, the second hole, the third hole and the fourth hole is a wedge-shaped hole. The wedge-shaped hole can also be explained in this way. Along the axial direction of the hole, The diameter of the hole changes linearly and can be called a wedge-shaped hole. Of course, the hole can also take on shapes such that the diameter of the hole changes non-linearly along the axis of the hole.

In addition, the aperture of the first hole of the first lens and the aperture of the third hole of the second lens may be set to be equal, or the aperture of the second hole of the first lens and the second lens may be made equal. The aperture of the fourth hole is set to be equal, or the aperture of the first hole of the first lens and the aperture of the third hole of the second lens are set to be equal, and the second hole of the first lens is set to be equal. The aperture is set equal to the aperture of the fourth hole of the second lens.

In the electrostatic lens described above, the first electrode layer 101 is connected to the first power terminal, and the second electrode layer 102 is connected to the second power terminal. In this way, when the first electrode layer 101 is loaded through the first power terminal When the voltage is applied, the same voltage can be applied to the first part of the first electrode layer and the second part of the first electrode layer at the same time. Similarly, when a voltage is applied to the second electrode layer 102 through the second power terminal, The same voltage can be applied to the first part of the second electrode layer and the second part of the second electrode layer at the same time.

The embodiment of the present application also provides another structure different from the above-mentioned electrostatic lens. As shown in Figure 30, the electrostatic lens 100 includes a stacked first electrode layer 101 and a second electrode layer 102, and the first electrode layer 101 and the second electrode layer 102 are insulated, for example, separated by a dielectric layer 3 to prevent the first electrode layer 101 and the second electrode layer 102 from being electrically connected.

Referring to Figure 31, Figure 31 is a view in the M direction of Figure 30. The first electrode layer 101 includes a first part A1 of the first electrode layer and a second part A2 of the first electrode layer. The first part A1 of the first electrode layer has a penetrating first electrode. In the first hole 201 of the layer 101, the second portion A2 of the first electrode layer has a second hole 202 penetrating through the first electrode layer 101. Also, the first part A1 of the first electrode layer and the second part A2 of the first electrode layer are insulated, for example, separated by the dielectric layer 3 to prevent the first part A1 of the first electrode layer from being separated from the second part A2 of the first electrode layer. The first part A1 of the first electrode layer is electrically connected to the first power terminal V1, and the second part A2 of the first electrode layer is electrically connected to the second power terminal V2.

Referring to Figure 32, Figure 32 is a view in the N direction of Figure 30. The second electrode layer 102 includes a first part B1 of the second electrode layer and a second part B2 of the second electrode layer. The first part B1 of the second electrode layer has a penetrating second electrode. In the third hole 203 of the layer 102, the second part B2 of the second electrode layer has a fourth hole 204 penetrating through the second electrode layer 102. In addition, the first part B1 of the second electrode layer and the second part B2 of the second electrode layer are insulated, for example, separated by the dielectric layer 3 to prevent the first part B1 of the second electrode layer from being separated from the second part B2 of the second electrode layer. The first part B1 of the second electrode layer is electrically connected to the third power terminal V3, and the second part B2 of the second electrode layer is electrically connected to the fourth power terminal V4.

As shown in Figure 30, the first part A1 of the first electrode layer and the first part B1 of the second electrode layer are arranged up and down along the stacking direction P, and the second part A2 of the first electrode layer and the second part B2 of the second electrode layer are also arranged along the stacking direction P. P is arranged up and down, the first hole 201 and the third hole 203 are connected, and the second hole 202 and the fourth hole 204 are connected.

The difference between the electrostatic lens shown in Figure 30 and any of the above electrostatic lenses is that in Figure 30, the first part A1 of the first electrode layer, the second part A2 of the first electrode layer, the first part B1 of the second electrode layer and the second Each part of the second part B2 of the electrode layer is connected to a power terminal, so that the first part A1 of the first electrode layer, the second part A2 of the first electrode layer, the first part B1 of the second electrode layer and the second part of the second electrode layer can be supplied. Part B2 is loaded with different voltages, so that the voltage difference between the first part A1 of the first electrode layer and the first part B1 of the second electrode layer is the same as the voltage between the second part A2 of the first electrode layer and the second part B2 of the second electrode layer. The difference may be the same or different. Furthermore, the field strength of the first lens and the field strength of the second lens may be the same or different.

Therefore, in the electrostatic lens shown in Figure 30, by controlling the voltage of different parts, the position of the focus point is changed, so that the electrostatic lens has strong flexibility and robustness, and can be applied to more Scenes. For example, a voltage of 15KV is applied to the first part A1 of the first electrode layer through the first power terminal V1, and a voltage of 8KV is applied to the first part B1 of the second electrode layer through the third power terminal V3. In this case, the first lens can be in a state of In the electric field, a focused point can be formed. The second part A2 of the first electrode layer is loaded with a voltage of 10Kv through the second power terminal V2, and a voltage of 2Kv is applied to the second part B2 of the second electrode layer through the fourth power terminal V4. In this case, the second lens can be in another state. into an electric field, thereby forming a focusing point at another location.

In particular, according to different application scenarios, that is, according to different sizes of defocus, different voltages are loaded on different parts, so that different shapes of focus surfaces can be flattened.

In the above-mentioned electrostatic lens shown in Figure 30, it can be combined with the imaging mechanism (changing the aperture) shown in Figure 15 to form other electrostatic lenses. For example, Figure 33 is based on Figure 30, the first lens The aperture S1 is set smaller than the aperture S2 of the second lens.

In addition, in the electrostatic lenses shown in FIGS. 30 and 33 , any one of the first hole, the second hole, the third hole, and the fourth hole may be a straight hole, a wedge-shaped hole, or a hole of other shapes.

In some alternative embodiments, in addition to the first electrode layer 101 and the second electrode layer 102, more electrode layers may be included. For example, the structure shown in FIG. 34 may also include a third electrode. The layer 103 and the fourth electrode layer 104, the first electrode layer 101 and the second electrode layer 102, the third electrode layer 103 and the fourth electrode layer 104 are stacked in sequence, and are dielectric between each two adjacent electrode layers. The layer 3 is isolated. In addition, the third electrode layer 104 forms a first part of the third electrode layer and a second part of the third electrode layer. The first part of the third electrode layer and the second part of the third electrode layer are separated by the dielectric layer 3 Open, the fourth electrode layer 104 forms a first part of the fourth electrode layer and a second part of the fourth electrode layer, and the first part of the fourth electrode layer and the second part of the fourth electrode layer are separated by the dielectric layer 3 .

For the electrostatic lens shown in Figure 34, during specific implementation, the first voltage can be loaded on the first part B1 of the second electrode layer 102 and the second part C2 of the third electrode layer 103, and at the same time The first part C1 of the third electrode layer 103 and the second part D2 of the fourth electrode layer 104 are loaded with a second voltage. The first voltage and the second voltage are not equal, and the remaining parts are not loaded with voltage. , that is, the first part B1 of the second electrode layer and the first part C1 of the third electrode layer constitute the first lens, and the second part C2 of the third electrode layer and the second part D2 of the fourth electrode layer constitute the second lens. Such an electrostatic lens The imaging mechanism can be determined by Gaussian imaging theorem.

Explain that since the focal length f1 of the first lens is equal to f2 of the second lens, and because the first lens is convex relative to the second lens, furthermore, the object distance U1 of the first lens and the object distance U2 of the second aperture lens are not equal, so that the image distance V1 of the first lens and the image distance V2 of the second aperture lens are not equal. Therefore, the focus point F1 of the first lens and the focus point of the second aperture lens will appear as shown in Figure 35. F2 is not in a straight line.

Figure 36 and Figure 37 respectively show the structural diagram of an electrostatic lens. The electrostatic lens includes six electrode layers. It can be seen from Figure 36 and Figure 37 that when voltage is applied to different parts of different electrode layers, the focus point The location is different.

Figure 38 shows the structural diagram of a multi-charged-particle beam multi-optical column adjusted by a single focusing module. In this multi-beam charged particle system, in addition to particle source 1, collimator 2 and split In addition to the beamer 3, an electrostatic lens 100 is also included. The electrostatic lens 100 here is formed based on the above-mentioned FIG. 36 or FIG. 37 , and the apertures of the respective holes in the electrostatic lens 100 are equal.

Figure 39 shows the structural diagram of another multi-charged-particle beam multi-optical column adjusted by a single focusing module. The difference between this structure and the multi-beam charged particle system shown in Figure 38 is that the electrostatic lens 100 The diameters of the individual holes in can be unequal.

Figure 40 shows the structural diagram of another multi-charged-particle beam multi-optical column multi-beam charged particle system adjusted by multiple focusing modules. The electrostatic lens in this structure includes a first electrostatic lens 101 and a second electrostatic lens 102. , wherein the first electrostatic lens 101 is based on the above-mentioned Gaussian imaging theorem

The second electrostatic lens 102 is formed based on the above-mentioned FIG. 36 or FIG. 37 .

Figure 41 shows the structural diagram of another multi-charged-particle beam multi-optical column multi-beam charged particle system adjusted by multiple focusing modules. The electrostatic lens in this structure includes a first electrostatic lens 101 and a second electrostatic lens 102. , wherein both the first electrostatic lens 101 and the second electrostatic lens 102 are formed based on the above-mentioned FIG. 36 or FIG. 37 .

For the multi-beam multi-column multi-beam charged particle system adjusted by multiple focusing modules shown in Figure 40 and Figure 41, the ability to adjust large field curvature is stronger.

Based on the above structural description of multiple electrostatic lenses, it can be summarized that the present application includes electrostatic lenses formed based on three different principles, as described below.

The first is through Gaussian imaging theorem

That is, by making the surface of the electrostatic lens facing the particle source a curved surface, the focusing position of the charged particle beam is adjusted to reduce the defocus difference of different charged particle beams, and ultimately the focusing surface can be flattened.

The second is to reduce the defocus difference of different charged particle beams by changing the size of the aperture in the electrostatic lens used to pass through the charged particle beam, and can also achieve flattening of the focusing surface.

The third method is to set the electrostatic lens as a multi-layer electrode layer that is insulated from each other, and make each electrode layer have multiple areas, and each two adjacent areas are also insulated. By loading different areas of different layers with different voltage to reduce the defocus difference of different charged particle beams and achieve flattening of the focusing surface.

The electrostatic lens of any of the above embodiments can be applied in a chip manufacturing process.

The following describes the chip manufacturing process, which mainly includes the following process steps: Step 1, make the wafer; Step 2, apply an anti-corrosion agent on the wafer surface; Step 3, use a multi-beam charged particle system to irradiate the charged particle beam to the anti-corrosion agent. on the etchant to form a pattern; step four, use an etching machine to etch N wells and P wells on the exposed silicon, and inject ions to form a PN junction (logic gate); step five, then use chemical and physical vapor phase The precipitation creates a metal connection circuit to make a chip.

In the process of the above-mentioned step three, the wafer can be engraved using the engraving system including an electrostatic lens provided in this application, such as an electron beam exposure machine. Figure 42 shows the structure of an engraving system. As shown in the figure, in addition to the above-mentioned multi-beam charged particle system, the engraving system also includes a stage 9, which can be used to install the object 7 to be etched, such as the wafer to be engraved, and also includes a biaser ( deflector) 6, which is used to control the etching position on the wafer to be etched. When the wafer is carved using the scribing system shown in Figure 42, particle source 1 generates charged particles, collimator 2 then collimates and expands the charged particles, and the collimated and expanded charged particle beam passes through The beam splitter 3 is divided into multiple beams, and the electrostatic lens 101 and the electrostatic lens 102 converge the multiple beams of charged particles, and under the action of the biaser 5, the charged particle beam is focused on the position on the wafer that needs to be engraved.

Among them, since the electrostatic lens 101 and the electrostatic lens 102 can correct the defocus distance, in this case, the charged particle beams passing through the electrostatic lens 101 and the electrostatic lens 102 can be converged on the wafer to be carved, which has a larger effect than the existing ones. The multi-beam charged particle system with different defocus can ensure that the charged particle beams are all concentrated on the wafer to be carved, rather than partially concentrated on the wafer to be carved and partially concentrated on top of the wafer to be carved. Therefore, using The engraving system provided in this application can shorten the engraving time and improve the engraving efficiency.

After completing the above-mentioned chip manufacturing, the following steps will also be included. Step one is to inspect the chip to check whether there are process defects in the chip; step two is to package the inspected chip. In the process of performing step one, an inspection system is required. Figure 43 shows a structural diagram of an inspection system. In addition to the above-mentioned multi-beam charged particle system, the inspection system also includes a station 9. The station 9 It can be used to install the object 7 to be inspected, such as the manufactured chip, and can also include a detector 8. The detector 8 is used to detect secondary charged particles generated by multiple beams of charged particles from the object 7 to be inspected to generate The signal corresponding to the secondary charged particles can be understood in this way. The electron beam generated by the multi-beam charged particle system is focused on the wafer to form an electron beam spot on the wafer. The detector 8 collects the secondary electrons generated on the surface of the wafer and the back Scatter electrons to obtain topography information of the wafer surface.

It should be noted that in FIG. 43 , it is schematically pointed out that the secondary charged particles generated by the object 7 to be inspected will be reflected into the detector 8 , and the transmission path of the secondary charged particles is not limited.

In the inspection system shown in Figure 43, since the electrostatic lens 101 and the electrostatic lens 102 can correct the defocus distance, in this case, the charged particle beams passing through the electrostatic lens 101 and the electrostatic lens 102 can be converged on the chip to be inspected. Compared with the existing multi-beam charged particle system with a larger defocus, it can ensure that the charged particle beams are all concentrated on the chip to be inspected, instead of partially converging on the chip to be inspected and partially converging on the chip to be inspected. , Therefore, by using the inspection system provided in this application, the chip morphology information obtained will be clearer and the acquisition efficiency will be faster.

In the description of this specification, specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

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. should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

An electrostatic lens, characterized by including:

first electrode layer;

a second electrode layer, the first electrode layer and the second electrode layer are stacked, and the first electrode layer and the second electrode layer are insulated;

The first electrode layer includes: a first part of the first electrode layer and a second part of the first electrode layer;

The second electrode layer includes: a first part of the second electrode layer and a second part of the second electrode layer;

The first part of the first electrode layer and the first part of the second electrode layer are arranged along the stacking direction, and the second part of the first electrode layer and the second part of the second electrode layer are arranged along the stacking direction. cloth;

The first part of the first electrode layer protrudes relative to the second part of the first electrode layer in a direction away from the second electrode layer;

A first hole penetrating the first electrode layer along the stacking direction is formed in the first part of the first electrode layer, and a first hole penetrating the first electrode layer along the stacking direction is formed in the second part of the first electrode layer. the second hole of the electrode layer;

A third hole connected to the first hole is opened in the first part of the second electrode layer, and a fourth hole connected to the second hole is opened in the second part of the second electrode layer.
The electrostatic lens according to claim 1, wherein the first part of the second electrode layer protrudes in a direction closer to the first electrode layer relative to the second part of the second electrode layer.
The electrostatic lens according to claim 1 or 2, characterized in that, along the stacking direction, the port of the first hole close to the third hole and the port of the third hole close to the first hole The distance between the ports is d1, the distance between the port of the second hole close to the fourth hole and the port of the fourth hole close to the second hole is d2, and d1=d2 .
The electrostatic lens according to claim 1, wherein the first part of the second electrode layer protrudes in a direction away from the first electrode layer relative to the second part of the second electrode layer.
The electrostatic lens according to claim 1, wherein the first part of the second electrode layer and the second part of the second electrode layer are in a first plane, and the first plane is perpendicular to the stacking direction. .
The electrostatic lens according to any one of claims 1 to 5, wherein the aperture of the first hole is not equal to the aperture of the second hole.
The electrostatic lens according to any one of claims 1 to 6, wherein the aperture of the first hole is equal to the aperture of the third hole;

and / or,

The diameter of the second hole is equal to the diameter of the fourth hole.
The electrostatic lens according to any one of claims 1 to 7, wherein any one of the first part of the first electrode layer and the second part of the first electrode layer is perpendicular to the stacking direction. It has a planar structure, and there is a step at the intersection between the first part of the first electrode layer and the second part of the first electrode layer.
The electrostatic lens according to any one of claims 1 to 8, characterized in that the electrostatic lens further includes:

A dielectric layer, the first electrode layer, the dielectric layer and the second electrode layer are stacked in sequence along the stacking direction;

The dielectric layer is provided with a hole connecting the first hole and the third hole, and a hole connecting the second hole and the fourth hole.
The electrostatic lens according to any one of claims 1 to 9, characterized in that the electrostatic lens further includes:

A first power terminal electrically connected to the first electrode layer;

The second power terminal is electrically connected to the second electrode layer.
A multi-beam charged particle system, characterized by including:

Particle source, used to generate charged particles;

The electrostatic lens according to any one of claims 1 to 10;

Wherein the electrostatic lens is arranged in the beam path of the charged particles.
The multi-beam charged particle system according to claim 11, characterized in that the multi-beam charged particle system is a multi-beam charged particle inspection system, and the multi-beam charged particle inspection system further includes:

A stage used to install the object to be inspected, and the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be inspected;

A detector used to detect secondary charged particles generated by the multi-beam charged particles from the object to be inspected, so as to generate signals corresponding to the secondary charged particles.
The multi-beam charged particle system according to claim 11, wherein the multi-beam charged particle system is a multi-beam charged particle mapping system, and the multi-beam charged particle mapping system further includes:

The stage is used to install the object to be carved, and the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be carved coated with the anti-corrosion agent to form a particle beam spot on the object to be carved. .
A method for multi-beam charged particle inspection of a substrate, characterized by including:

Use particle sources to generate charged particles;

Focusing the multi-beam charged particles on the substrate using an electrostatic lens arranged in the beam path of the charged particles;

detecting secondary charged particles generated by the multi-fractionated charged particles from the substrate to generate signals corresponding to the secondary charged particles;

Wherein, the electrostatic lens includes a stacked and insulated first electrode layer and a second electrode layer, the first electrode layer includes a first part of the first electrode layer and a second part of the first electrode layer, and the second electrode layer It includes a first part of the second electrode layer and a second part of the second electrode layer. The first part of the first electrode layer has a first hole. The second part of the first electrode layer has a second hole. The second electrode The first part of the layer has a third hole connected to the first hole, the second part of the second electrode layer has a fourth hole connected to the second hole, and the first part of the first electrode layer The second portion protrudes relative to the first electrode layer in a direction away from the second electrode layer;

Using an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the substrate includes:

causing the first charged particle beam in the multiple beams of charged particles to pass through the connected first hole and the third hole and focus on the substrate;

The second charged particle beam in the multiple beams of charged particles is focused on the substrate through the connected second hole and the fourth hole.
The inspection method according to claim 14, wherein the electrostatic lens further includes: a first power terminal and a second power terminal, the first power terminal is electrically connected to the first electrode layer, and the third power terminal is electrically connected to the first electrode layer. Two power terminals are electrically connected to the second electrode layer;

Using an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the substrate further includes:

Loading a first voltage to the first electrode layer through the first power terminal;

A second voltage that is not equal to the first voltage is loaded on the second electrode layer through the second power terminal.
The inspection method according to claim 14 or 15, characterized in that the diameter of the first hole and the diameter of the second hole are not equal.
The inspection method according to any one of claims 14 to 16, characterized in that the first part of the second electrode layer protrudes in a direction closer to the first electrode layer relative to the second part of the second electrode layer. , along the stacking direction, the distance between the port of the first hole close to the third hole and the port of the third hole close to the first hole is d1, and the distance between the port of the second hole and the port of the third hole close to the first hole is d1. The distance between the port of the fourth hole and the port of the fourth hole close to the second hole is d2, and d1=d2.
The inspection method according to any one of claims 14 to 16, characterized in that the first part of the second electrode layer protrudes in a direction away from the first electrode layer relative to the second part of the second electrode layer. .
The inspection method according to any one of claims 14 to 16, characterized in that the first part of the second electrode layer and the second part of the second electrode layer are in a first plane, and the first plane perpendicular to the stacking direction.
A method for engraving on an object coated with an anti-corrosion agent, characterized by comprising:

Use particle sources to generate charged particles;

Utilizing an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the object to be engraved coated with the anti-corrosion agent to form a particle beam spot on the object to be engraved;

Wherein, the electrostatic lens includes a stacked and insulated first electrode layer and a second electrode layer, the first electrode layer includes a first part of the first electrode layer and a second part of the first electrode layer, and the second electrode layer It includes a first part of the second electrode layer and a second part of the second electrode layer. The first part of the first electrode layer has a first hole. The second part of the first electrode layer has a second hole. The second electrode The first part of the layer has a third hole connected to the first hole, the second part of the second electrode layer has a fourth hole connected to the second hole, and the first part of the first electrode layer The second portion protrudes relative to the first electrode layer in a direction away from the second electrode layer;

The use of an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the object to be carved includes:

causing the first charged particle beam in the multiple beams of charged particles to pass through the connected first hole and the third hole and focus on the object to be carved;

The second charged particle beam in the multiple beams of charged particles is focused on the object to be carved through the connected second hole and the fourth hole.
The method of engraving according to claim 20, wherein the electrostatic lens further includes: a first power terminal and a second power terminal, the first power terminal is electrically connected to the first electrode layer, and the The second power terminal is electrically connected to the second electrode layer;

The use of an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the object to be carved further includes:

Loading a first voltage to the first electrode layer through the first power terminal;

A second voltage that is not equal to the first voltage is loaded on the second electrode layer through the second power terminal.
The engraving method according to claim 20 or 21, characterized in that the diameter of the first hole and the diameter of the second hole are not equal.
The method of engraving according to any one of claims 20 to 22, wherein the first part of the second electrode layer is convex relative to the second part of the second electrode layer in a direction closer to the first electrode layer. Out, along the stacking direction, the distance between the port of the first hole close to the third hole and the port of the third hole close to the first hole is d1, and the distance between the second hole The distance between the port close to the fourth hole and the port of the fourth hole close to the second hole is d2, and d1=d2.
The method of engraving according to any one of claims 20 to 22, wherein the first part of the second electrode layer protrudes in a direction away from the first electrode layer relative to the second part of the second electrode layer. out.
The method of engraving according to any one of claims 20 to 22, wherein the first part of the second electrode layer and the second part of the second electrode layer are in a first plane, and the first part The plane is perpendicular to the stacking direction.
An electrostatic lens, characterized by including:

first electrode layer;

a second electrode layer, the first electrode layer and the second electrode layer are stacked, and the first electrode layer and the second electrode layer are insulated;

The first electrode layer includes: a first part of the first electrode layer and a second part of the first electrode layer, and the first part of the first electrode layer and the second part of the first electrode layer are insulated;

The second electrode layer includes: a first part of the second electrode layer and a second part of the second electrode layer, and the first part of the second electrode layer and the second part of the second electrode layer are insulated;

The first part of the first electrode layer and the first part of the second electrode layer are arranged along the stacking direction, and the second part of the first electrode layer and the second part of the second electrode layer are arranged along the stacking direction. cloth;

A first hole penetrating the first electrode layer along the stacking direction is formed in the first part of the first electrode layer, and a first hole penetrating the first electrode layer along the stacking direction is formed in the second part of the first electrode layer. the second hole of the electrode layer;

A third hole connected to the first hole is opened in the first part of the second electrode layer, and a fourth hole connected to the second hole is opened in the second part of the second electrode layer;

The electrostatic lens also includes:

A first power terminal electrically connected to the first part of the first electrode layer;

a second power terminal electrically connected to the second part of the first electrode layer;

A third power terminal electrically connected to the first part of the second electrode layer;

The fourth power terminal is electrically connected to the second part of the second electrode layer.
The electrostatic lens according to claim 26, wherein the first part of the first electrode layer and the second part of the first electrode layer are in a first plane, and the first part of the second electrode layer and the second part of the first electrode layer are in a first plane. The second part of the two electrode layers is in a second plane, and both the first plane and the second plane are perpendicular to the stacking direction.
The electrostatic lens according to claim 26 or 27, characterized in that the aperture of the first hole and the aperture of the second hole are not equal.
The electrostatic lens according to any one of claims 26 to 28, wherein the aperture of the first hole is equal to the aperture of the third hole;

and / or,

The diameter of the second hole is equal to the diameter of the fourth hole.
The electrostatic lens according to any one of claims 26 to 29, characterized in that the electrostatic lens further includes:

A first dielectric layer, the first electrode layer, the first dielectric layer and the second electrode layer are stacked sequentially along the stacking direction;

The first dielectric layer is provided with a hole connecting the first hole and the third hole, and a hole connecting the second hole and the fourth hole;

The second dielectric layer is formed between the first part of the first electrode layer and the second part of the first electrode layer, and between the first part of the second electrode layer and the second part of the second electrode layer. separated by a second dielectric layer.
A multi-beam charged particle system, characterized by including:

Particle source, used to generate charged particles;

The electrostatic lens according to any one of claims 26 to 30;

Wherein the electrostatic lens is arranged in the beam path of the charged particles.
The multi-beam charged particle system according to claim 31, characterized in that the multi-beam charged particle system is a multi-beam charged particle inspection system, and the multi-beam charged particle inspection system further includes:

A stage used to install the object to be inspected, and the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be inspected;

A detector used to detect secondary charged particles generated by the multi-beam charged particles from the object to be inspected, so as to generate signals corresponding to the secondary charged particles.
The multi-beam charged particle system according to claim 31, wherein the multi-beam charged particle system is a multi-beam charged particle mapping system, and the multi-beam charged particle mapping system further includes:

The stage is used to install the object to be carved, and the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be carved coated with the anti-corrosion agent to form a particle beam spot on the object to be carved. .
A method for multi-beam charged particle inspection of a substrate, characterized by including:

Use particle sources to generate charged particles;

Focusing the multi-beam charged particles on the substrate using an electrostatic lens arranged in the beam path of the charged particles;

detecting secondary charged particles generated by the multi-fractionated charged particles from the substrate to generate signals corresponding to the secondary charged particles;

Wherein, the electrostatic lens includes a stacked and insulated first electrode layer and a second electrode layer, the first electrode layer includes an insulated first part of the first electrode layer and a second part of the first electrode layer, and the third The two electrode layers include a first part of an insulated second electrode layer and a second part of the second electrode layer. The first part of the first electrode layer is provided with a first hole, and the second part of the first electrode layer is provided with a second hole. , the first part of the second electrode layer is provided with a third hole connected to the first hole, and the second part of the second electrode layer is provided with a fourth hole connected to the second hole;

Using an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the substrate includes:

Loading different voltages on the first part of the first electrode layer, the second part of the first electrode layer, the first part of the second electrode layer and the second part of the second electrode layer;

causing the first charged particle beam in the multiple beams of charged particles to pass through the connected first hole and the third hole and focus on the substrate;

The second charged particle beam in the multiple beams of charged particles is focused on the substrate through the connected second hole and the fourth hole.
The inspection method according to claim 34, characterized in that the diameter of the first hole and the diameter of the second hole are not equal.
A method for engraving on an object coated with an anti-corrosion agent, characterized by comprising:

Use particle sources to generate charged particles;

Utilizing an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the object to be engraved coated with the anti-corrosion agent to form a particle beam spot on the object;

Wherein, the electrostatic lens includes a stacked and insulated first electrode layer and a second electrode layer, the first electrode layer includes an insulated first part of the first electrode layer and a second part of the first electrode layer, and the third The two electrode layers include a first part of an insulated second electrode layer and a second part of the second electrode layer. The first part of the first electrode layer is provided with a first hole, and the second part of the first electrode layer is provided with a second hole. , the first part of the second electrode layer is provided with a third hole connected to the first hole, and the second part of the second electrode layer is provided with a fourth hole connected to the second hole;

The use of an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the object to be carved includes:

Loading different voltages on the first part of the first electrode layer, the second part of the first electrode layer, the first part of the second electrode layer and the second part of the second electrode layer;

causing the first charged particle beam in the multiple beams of charged particles to pass through the connected first hole and the third hole and focus on the object to be carved;

The second charged particle beam in the multiple beams of charged particles is focused on the object to be carved through the connected second hole and the fourth hole.
The engraving method according to claim 36, wherein the diameter of the first hole is not equal to the diameter of the second hole.
An electrostatic lens, characterized by including:

first electrode layer;

a second electrode layer, the first electrode layer and the second electrode layer are stacked, and the first electrode layer and the second electrode layer are insulated;

The first electrode layer includes: a first part of the first electrode layer and a second part of the first electrode layer;

The second electrode layer includes: a first part of the second electrode layer and a second part of the second electrode layer;

The first part of the first electrode layer and the first part of the second electrode layer are arranged along the stacking direction, and the second part of the first electrode layer and the second part of the second electrode layer are arranged along the stacking direction. cloth;

A first hole penetrating the first electrode layer along the stacking direction is formed in the first part of the first electrode layer, and a first hole penetrating the first electrode layer along the stacking direction is formed in the second part of the first electrode layer. the second hole of the electrode layer;

A third hole connected to the first hole is opened in the first part of the second electrode layer, and a fourth hole connected to the second hole is opened in the second part of the second electrode layer;

Wherein, the diameter of the first hole is not equal to the diameter of the second hole.
The electrostatic lens according to claim 38, wherein the aperture of the first hole is equal to the aperture of the third hole;

and / or,

The diameter of the second hole is equal to the diameter of the fourth hole.
The electrostatic lens according to claim 38 or 39, wherein the first part of the first electrode layer and the second part of the first electrode layer are in a first plane, and the first part of the second electrode layer and the second part of the first electrode layer are in a first plane. The second part of the second electrode layer is located in a second plane, and both the first plane and the second plane are perpendicular to the stacking direction.
The electrostatic lens according to any one of claims 38 to 40, characterized in that the electrostatic lens further includes:

A dielectric layer, the first electrode layer, the dielectric layer and the second electrode layer are stacked in sequence along the stacking direction;

The dielectric layer is provided with a hole connecting the first hole and the third hole, and a hole connecting the second hole and the fourth hole.
The electrostatic lens according to any one of claims 38 to 41, wherein the electrostatic lens further includes:

A first power terminal electrically connected to the first electrode layer;

The second power terminal is electrically connected to the second electrode layer.
A multi-beam charged particle system, characterized by including:

Particle source, used to generate charged particles;

The electrostatic lens according to any one of claims 38 to 42;

Wherein the electrostatic lens is arranged in the beam path of the charged particles.
The multi-beam charged particle system according to claim 43, characterized in that the multi-beam charged particle system is a multi-beam charged particle inspection system, and the multi-beam charged particle inspection system further includes:

A stage used to install the object to be inspected, and the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be inspected;

A detector used to detect secondary charged particles generated by the multi-beam charged particles from the object to be inspected, so as to generate signals corresponding to the secondary charged particles.
The multi-beam charged particle system according to claim 43, wherein the multi-beam charged particle system is a multi-beam charged particle mapping system, and the multi-beam charged particle mapping system further includes:

The stage is used to install the object to be carved, and the multi-beam charged particles after passing through the electrostatic lens are focused on the object to be carved coated with the anti-corrosion agent to form a particle beam spot on the object to be carved. .
A method for multi-beam charged particle inspection of a substrate, characterized by including:

Use particle sources to generate charged particles;

Focusing the multi-beam charged particles on the substrate using an electrostatic lens arranged in the beam path of the charged particles;

detecting secondary charged particles generated by the multi-fractionated charged particles from the substrate to generate signals corresponding to the secondary charged particles;

Wherein, the electrostatic lens includes a stacked and insulated first electrode layer and a second electrode layer, the first electrode layer includes an insulated first part of the first electrode layer and a second part of the first electrode layer, and the third The two electrode layers include a first part of an insulated second electrode layer and a second part of the second electrode layer. The first part of the first electrode layer is provided with a first hole, and the second part of the first electrode layer is provided with a second hole. , the first part of the second electrode layer is provided with a third hole connected to the first hole, the second part of the second electrode layer is provided with a fourth hole connected to the second hole, the The aperture of the first hole is not equal to the aperture of the second hole;

Using an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the substrate includes:

causing the first charged particle beam in the multiple beams of charged particles to pass through the connected first hole and the third hole and focus on the substrate;

The second charged particle beam in the multiple beams of charged particles is focused on the substrate through the connected second hole and the fourth hole.
The inspection method according to claim 46, wherein the electrostatic lens further includes: a first power terminal and a second power terminal, the first power terminal is electrically connected to the first electrode layer, and the third power terminal is electrically connected to the first electrode layer. Two power terminals are electrically connected to the second electrode layer;

Using an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the substrate further includes:

Loading a first voltage to the first electrode layer through the first power terminal;

A second voltage that is not equal to the first voltage is loaded on the second electrode layer through the second power terminal.
A method for engraving on an object coated with an anti-corrosion agent, characterized by comprising:

Use particle sources to generate charged particles;

Utilizing an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the object to be engraved coated with the anti-corrosion agent to form a particle beam spot on the object;

Wherein, the electrostatic lens includes a stacked and insulated first electrode layer and a second electrode layer, the first electrode layer includes an insulated first part of the first electrode layer and a second part of the first electrode layer, and the third The two electrode layers include a first part of an insulated second electrode layer and a second part of the second electrode layer. The first part of the first electrode layer is provided with a first hole, and the second part of the first electrode layer is provided with a second hole. , the first part of the second electrode layer is provided with a third hole connected to the first hole, the second part of the second electrode layer is provided with a fourth hole connected to the second hole, the The aperture of the first hole is not equal to the aperture of the second hole;

Using an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the object to be carved includes:

causing the first charged particle beam in the multiple beams of charged particles to pass through the connected first hole and the third hole and focus on the object to be carved;

The second charged particle beam in the multiple beams of charged particles is focused on the object to be carved through the connected second hole and the fourth hole.
The method of engraving according to claim 48, wherein the electrostatic lens further includes: a first power terminal and a second power terminal, the first power terminal is electrically connected to the first electrode layer, and the The second power terminal is electrically connected to the second electrode layer;

The use of an electrostatic lens arranged in the beam path of the charged particles to focus the multi-beam charged particles on the object to be carved also includes:

Loading a first voltage to the first electrode layer through the first power terminal;

A second voltage that is not equal to the first voltage is loaded on the second electrode layer through the second power terminal.