Systems and assemblies for mitigating arcing energy in charged particle systems

Abstract

Systems and assemblies for reducing arcing energy a charged particle system (400). Systems and assemblies may include a plurality of cables (422, 424, 426, 428) coupled between a high voltage source (410) and a charged particle source (430); a first component (441) providing impedance at first ends of the plurality of cables; and a second component (442) providing impedance at second ends of the plurality of cables, wherein the first component and the second component are configured to mitigate arcing energy provided to the charged particle source. Systems and assemblies may include a cable configured to be coupled between a high voltage source and a wafer; and a component comprising an impedance in the cable, the component comprising the impedance configured to be coupled to the wafer, wherein the component comprising the impedance is configured to mitigate arcing energy provided to the wafer.

Description

SYSTEMS AND ASSEMBLIES FOR MITIGATING ARCING ENERGY IN CHARGEDPARTICLE SYSTEMSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority of WO application PCT / CN2024 / 114615 which was filed on August 26, 2024 and WO application PCT / CN2025 / 075305 which was filed on January 26, 2025 which are incorporated herein in its entirety by reference.FIELD

[0002] The description herein relates to the field of charged particle systems, and more particularly to assemblies for mitigating arcing energy in charged particle systems.BACKGROUND

[0003] In manufacturing processes of integrated circuits (ICs), unfinished or finished circuit components are inspected to ensure that they are manufactured according to design and are free of defects. An inspection system utilizing an optical microscope typically has resolution down to a few hundred nanometers; and the resolution is limited by the wavelength of light. As the physical sizes of IC components continue to reduce down to sub-100 or even sub-10 nanometers, inspection systems capable of higher resolution than those utilizing optical microscopes are needed.

[0004] A charged particle (e.g., electron) beam microscope, such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM), capable of resolution down to less than a nanometer, serves as a practicable tool for inspecting IC components having a feature size that is sub- 100 nanometers. With a SEM, electrons of a single primary electron beam, or electrons of a plurality of primary electron beams, can be focused on locations of interest of a wafer under inspection. The primary electrons interact with the wafer and may be backscattered or may cause the wafer to emit secondary electrons. The intensity of the electron beams comprising the backscattered electrons and the secondary electrons may vary based on the properties of the internal and external structures of the wafer, and thereby may indicate whether the wafer has defects.SUMMARY

[0005] Embodiments of the present disclosure provide systems and assemblies for reducing arcing energy in a charged particle system. Systems and assemblies may include a plurality of cables coupled between a high voltage source and a charged particle source; a first component providing impedance at first ends of the plurality of cables; and a second component providing impedance at second ends of the plurality of cables, wherein the first component and the second component are configured to mitigate arcing energy provided to the charged particle source.

[0006] Systems and assemblies may include a cable configmed to be coupled between a high voltage source and a wafer; and a component comprising an impedance in the cable, the component comprising the impedance configured to be coupled to the wafer, wherein the component comprising the impedance is configmed to mitigate arcing energy provided to the wafer.

[0007] Systems and assemblies may include a first component comprising an impedance coupled with a high voltage somce and a first end of a plurality of cables; and a second component comprising an impedance coupled with a second end of the plurality of cables and a charged particle somce, wherein the first component and the second component are configured to mitigate damage to the charged particle source.

[0008] Systems and assemblies may include a component comprising an impedance configured to be coupled to a cable and a wafer, wherein the component is configmed to mitigate damage to the wafer.

[0009] Systems and assemblies may include an electrical coupling mechanism configured to couple a high voltage somce to a charged particle tool, the electrical coupling mechanism comprising: a cable from the high voltage source, and an impedance component coupled to the charged particle tool and configmed to mitigate arcing energy provided by the cable to the charged particle tool.

[0010] Systems and assemblies may include an electrical coupling mechanism configured to couple to a charged particle tool, the electrical coupling mechanism comprising: a cable, and an impedance component coupled to the cable and to the charged particle tool wherein the impedance component is configmed to mitigate damage to the charged particle tool.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Fig. 1 is a schematic diagram illustrating an exemplary electron beam inspection (EBI) system, consistent with embodiments of the present disclosure.

[0012] Fig. 2A is a schematic diagram illustrating an exemplary multi-beam system that is part of the exemplary charged particle beam inspection system of Fig. 1, consistent with embodiments of the present disclosme.

[0013] Fig. 2B is a schematic diagram illustrating an exemplary single-beam system that is part of the exemplary charged particle beam inspection system of Fig. 1, consistent with embodiments of the present disclosure.

[0014] Fig. 3 shows an example diagram of a charged particle source system.

[0015] Fig. 4 shows an example diagram of a charged particle source system, consistent with embodiments of the present disclosure.

[0016] Fig. 5 shows a diagram of a circuit with a protection circuit, consistent with embodiments of the present disclosure.

[0017] Fig. 6 shows a schematic diagram illustrating an exemplary electron beam inspection (EBI) system.

[0018] Fig. 7 shows a schematic diagram illustrating an exemplary electron beam inspection (EBI) system, consistent with embodiments of the present disclosure.DETAILED DESCRIPTION

[0019] Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings in which the same numbers in different drawings represent the same or similar elements unless otherwise represented. The implementations set forth in the following description of exemplary embodiments do not represent all implementations consistent with the disclosure. Instead, they are merely examples of apparatuses and methods consistent with aspects related to the subject matter recited in the appended claims. For example, although some embodiments are described in the context of utilizing electron beams, the disclosure is not so limited. Other types of charged particle beams may be similarly applied. Furthermore, other imaging systems may be used, such as optical imaging, photodetection, x-ray detection, extreme ultraviolet inspection, deep ultraviolet inspection, or the like, in which they generate corresponding types of images.

[0020] Electronic devices are constructed of circuits formed on a piece of silicon called a substrate. Many circuits may be formed together on the same piece of silicon and are called integrated circuits or ICs. The size of these circuits has decreased dramatically so that many more of them can fit on the substrate. For example, an IC chip in a smart phone can be as small as a thumbnail and yet may include over 2 billion transistors, the size of each transistor being less than 1 / 1000th the size of a human hair.

[0021] Making these extremely small ICs is a complex, time-consuming, and expensive process, often involving hundreds of individual steps. Errors in even one step have the potential to result in defects in the finished IC rendering it useless. Thus, one goal of the manufacturing process is to avoid such defects to maximize the number of functional ICs made in the process, that is, to improve the overall yield of the process.

[0022] One component of improving yield is monitoring the chip making process to ensure that it is producing a sufficient number of functional ICs. One way to monitor the process is to inspect the chip circuit structures at various stages of their formation. Inspection may be carried out using a scanning electron microscope (SEM). A SEM can be used to image these extremely small structures, in effect, taking a “picture” of the structures of the wafer. The image can be used to determine if the structure was formed properly, and also if it was formed at the proper location. If the structure is defective, then the process can be adjusted so the defect is less likely to recur. Defects may be generated during various stages of semiconductor processing. For the reason stated above, it is important to find defects accurately and efficiently as early as possible.

[0023] The working principle of a SEM is similar to a camera. A camera takes a picture by receiving and recording brightness and colors of light reflected or emitted from people or objects. A SEM takesa “picture” by receiving and recording energies or quantities of electrons reflected or emitted from the structures. Before taking such a “picture,” an electron beam may be projected onto the structures, and when the electrons are reflected or emitted (“exiting”) from the structures, a detector of the SEM may receive and record the energies or quantities of those electrons to generate an image. To take such a “picture,” some SEMs use a single electron beam (referred to as a “single-beam SEM”), while some SEMs use multiple electron beams (referred to as a “multi-beam SEM”) to take multiple “pictures” of the wafer. By using multiple electron beams, the SEM may project more electron beams onto the structures for obtaining these multiple “pictures,” resulting in more electrons exiting from the structures. Accordingly, the detector may receive more exiting electrons simultaneously, and generate images of the structures of the wafer with a higher efficiency and a faster speed.

[0024] The electron source is a key module of an electron beam system. The high voltage electron source module provides the necessary high voltage and heating current for electron source emission. The parts of the electron source operate in a vacuum environment with high temperature and high voltage. Typical systems, however, suffer from constraints. In typical systems, electron arcing occurs between different parts of the electron source due to vacuum down, particle pollution, etc. (see, e.g., arcing energy sources in high voltage module 310, cables 322, 324, 326, and 328, and electron source 330 of Fig. 3; arcing energy sources in HWSB 610, HWEB 620, cables 652, 654, 656, 676, 678, 680, 682, 684, 658, No.5 plate 612, HVSP 614, components related to e-chuck 622, other high voltage components of Fig. 6). This arcing energy may damage the tip of the electron source, other components in the SEM, or even the sample being inspected (e.g., a semiconductor wafer).

[0025] Additionally, typical systems do not have a protection circuit to avoid high currents flowing through the inspection wafer in the event of discharge in the system. Without current protection, wafer damage can be introduced after a discharge in the electron beam system. Due to capacitive coupling between the parts of the high voltage system, the total cable capacitance (energy stored in high voltage cable capacitances) can provide a large current sufficient to melt silicon, thereby damaging the wafer. Additionally, since arcing energy sources may be on different high voltage channels, they may cause secondary arcing between different components, including at critical positions in the charged particle system.

[0026] Some of the disclosed embodiments provide systems and methods that address some or all of these disadvantages by reducing arcing energy in charged particle systems. The disclosed embodiments may include cables coupled between a high voltage source and a charged particle source, where a first impedance (e.g., resistors) is at a first end of the cables and a second impedance (e.g., resistors, inductors, diodes, etc.) is at a second end of the cables. The first impedance may be coupled between the high voltage source and the first end of the cables to mitigate arcing energy from the high voltage source. The second impedance may be coupled between the second end of the cables and the charged particle source to mitigate arcing energy from the cables. The combined firstimpedance and second impedance may reduce the arcing energy provided to the charged particle source, thereby mitigating damage to the tip of the charged particle source.

[0027] The disclosed embodiments may include an impedance (e.g., a protection circuit) in cables configured to be coupled between a high voltage source (e.g., e-chuck box) and a wafer of a wafer holder (e.g., e-chuck). The impedance may be configured to be coupled to the wafer such that arcing energy provided to the wafer is mitigated. As a result, damage to the wafer may be mitigated.

[0028] The disclosed embodiments may include an electrical coupling mechanism coupled to a charged particle tool, where the electrical coupling mechanism includes high voltage cables and an impedance (e.g., resistors, inductors, diodes, etc.) coupled to the high voltage cables and the charged particle tool (e.g., a wafer of the charged particle tool, a wafer stage of the charged particle tool, plates of the charged particle tool, etc.). The high voltage cables may be coupled between high voltage modules and the charged particle tool. The impedance may be configured to mitigate arcing energy provided to the charged particle tool, including primary arcing and secondary arcing. As a result, damage to the charged particle tool may be mitigated.

[0029] Relative dimensions of components in drawings may be exaggerated for clarity. Within the following description of drawings, the same or like reference numbers refer to the same or like components or entities, and only the differences with respect to the individual embodiments are described.

[0030] As used herein, unless specifically stated otherwise, the term “or” encompasses all possible combinations, except where infeasible. For example, if it is stated that a component may include A or B, then, unless specifically stated otherwise or infeasible, the component may include A, or B, or A and B. As a second example, if it is stated that a component may include A, B, or C, then, unless specifically stated otherwise or infeasible, the component may include A, or B, or C, or A and B, or A and C, or B and C, or A and B and C.

[0031] Without limiting the scope of the present disclosure, some embodiments may be described in the context of providing detectors and detection methods in systems utilizing electron beams. However, the disclosure is not so limited. Other types of charged particle beams may be similarly applied. Furthermore, systems and methods for detection may be used in other imaging systems, such as optical imaging, photon detection, x-ray detection, ion detection, etc.

[0032] Fig. 1 illustrates an exemplary electron beam inspection (EBI) system 100 consistent with embodiments of the present disclosure. EBI system 100 may be used for imaging. As shown in Fig. 1, EBI system 100 includes a main chamber 101, a load / lock chamber 102, an electron beam tool 104, and an equipment front end module (EFEM) 106. Electron beam tool 104 is located within main chamber 101. EFEM 106 includes a first loading port 106a and a second loading port 106b. EFEM 106 may include additional loading port(s). First loading port 106a and second loading port 106b receive wafer front opening unified pods (FOUPs) that contain wafers (e.g., semiconductor wafers orwafers made of other material(s)) or samples to be inspected (wafers and samples may be used interchangeably). A “lot” is a plurality of wafers that may be loaded for processing as a batch.

[0033] One or more robotic arms (not shown) in EFEM 106 may transport the wafers to load / lock chamber 102. Load / lock chamber 102 is connected to a load / lock vacuum pump system (not shown) which removes gas molecules in load / lock chamber 102 to reach a first pressure below the atmospheric pressure. After reaching the first pressure, one or more robotic arms (not shown) may transport the wafer from load / lock chamber 102 to main chamber 101. Main chamber 101 is connected to a main chamber vacuum pump system (not shown) which removes gas molecules in main chamber 101 to reach a second pressure below the first pressure. After reaching the second pressure, the wafer is subject to inspection by electron beam tool 104. Electron beam tool 104 may be a single-beam system or a multi-beam system.

[0034] A controller 109 is electronically connected to electron beam tool 104. Controller 109 may be a computer configured to execute various controls of EBI system 100. While controller 109 is shown in Fig. 1 as being outside of the structure that includes main chamber 101, load / lock chamber 102, and EFEM 106, it is appreciated that controller 109 may be a part of the structure.

[0035] In some embodiments, controller 109 may include one or more processors (not shown). A processor may be a generic or specific electronic device capable of manipulating or processing information. For example, the processor may include any combination of any number of a central processing unit (or “CPU”), a graphics processing unit (or “GPU”), an optical processor, a programmable logic controllers, a microcontroller, a microprocessor, a digital signal processor, an intellectual property (IP) core, a Programmable Logic Array (PLA), a Programmable Array Logic (PAL), a Generic Array Logic (GAL), a Complex Programmable Logic Device (CPLD), a Field- Programmable Gate Array (FPGA), a System On Chip (SoC), an Application-Specific Integrated Circuit (ASIC), a neural processing unit (NPU), and any type of circuit capable of data processing. The processor may also be a virtual processor that includes one or more processors distributed across multiple machines or devices coupled via a network.

[0036] In some embodiments, controller 109 may further include one or more memories (not shown). A memory may be a generic or specific electronic device capable of storing codes and data accessible by the processor (e.g., via a bus). For example, the memory may include any combination of any number of a random-access memory (RAM), a read-only memory (ROM), an optical disc, a magnetic disk, a hard drive, a solid-state drive, a flash drive, a security digital (SD) card, a memory stick, a compact flash (CF) card, or any type of storage device. The codes may include an operating system (OS) and one or more application programs (or “apps”) for specific tasks. The memory may also be a virtual memory that includes one or more memories distributed across multiple machines or devices coupled via a network.

[0037] Embodiments of this disclosure may provide a single charged-particle beam imaging system (“single-beam system”). Compared with a single-beam system, a multiple charged-particle beamimaging system (“multi-beam system”) may be designed to optimize throughput for different scan modes. Embodiments of this disclosure provide a multi-beam system with the capability of optimizing throughput for different scan modes by using beam arrays with different geometries and adapting to different throughputs and resolution requirements.

[0038] Reference is now made to Fig. 2A, which is a schematic diagram illustrating an exemplary electron beam tool 104 including a multi-beam inspection tool that is part of the EBI system 100 of Fig. 1, consistent with embodiments of the present disclosure. In some embodiments, electron beam tool 104 may be operated as a single-beam inspection tool that is part of EBI system 100 of Fig. 1. Multi-beam electron beam tool 104 (also referred to herein as apparatus 104) comprises an electron source 201, a Coulomb aperture plate (or “gun aperture plate”) 271, a condenser lens 210, a source conversion unit 220, a primary projection system 230, a motorized stage 209, and a sample holder 207 supported by motorized stage 209 to hold a sample 208 (e.g., a wafer or a photomask) to be inspected. Multi-beam electron beam tool 104 may further comprise a secondary projection system 250 and an electron detection device 240. Primary projection system 230 may comprise an objective lens 231. Electron detection device 240 may comprise a plurality of detection elements 241, 242, and 243. A beam separator 233 and a deflection scanning unit 232 may be positioned inside primary projection system 230.

[0039] Electron source 201, Coulomb aperture plate 271, condenser lens 210, source conversion unit 220, beam separator 233, deflection scanning unit 232, and primary projection system 230 may be aligned with a primary optical axis 204 of apparatus 104. Secondary projection system 250 and electron detection device 240 may be aligned with a secondary optical axis 251 of apparatus 104.

[0040] Electron source 201 may comprise a cathode (not shown) and an extractor or anode (not shown), in which, during operation, electron source 201 is configured to emit primary electrons from the cathode and the primary electrons are extracted or accelerated by the extractor and / or the anode to form a primary electron beam 202 that form a primary beam crossover (virtual or real) 203. Primary electron beam 202 may be visualized as being emitted from primary beam crossover 203.

[0041] Source conversion unit 220 may comprise an image-forming element array (not shown), an aberration compensator array (not shown), a beam-limit aperture array (not shown), and a pre-bending micro-deflector array (not shown). In some embodiments, the pre-bending micro-deflector array deflects a plurality of primary beamlets 211, 212, 213 of primary electron beam 202 to normally enter the beam-limit aperture array, the image-forming element array, and an aberration compensator array. In some embodiments, apparatus 104 may be operated as a single-beam system such that a single primary beamlet is generated. In some embodiments, condenser lens 210 is designed to focus primary electron beam 202 to become a parallel beam and be normally incident onto source conversion unit 220. The image-forming element array may comprise a plurality of micro-deflectors or micro-lenses to influence the plurality of primary beamlets 211, 212, 213 of primary electron beam 202 and to form a plurality of parallel images (virtual or real) of primary beam crossover 203, one for each of theprimary beamlets 211, 212, and 213. In some embodiments, the aberration compensator array may comprise a field curvature compensator array (not shown) and an astigmatism compensator array (not shown). The field curvature compensator array may comprise a plurality of micro-lenses to compensate field curvature aberrations of the primary beamlets 211, 212, and 213. The astigmatism compensator array may comprise a plurality of micro-stigmators to compensate astigmatism aberrations of the primary beamlets 211, 212, and 213. The beam-limit aperture array may be configured to limit diameters of individual primary beamlets 211, 212, and 213. Fig. 2A shows three primary beamlets 211, 212, and 213 as an example, and it is appreciated that source conversion unit 220 may be configured to form any number of primary beamlets. Controller 109 may be connected to various parts of EBI system 100 of Fig. 1, such as source conversion unit 220, electron detection device 240, primary projection system 230, or motorized stage 209. In some embodiments, as explained in further details below, controller 109 may perform various image and signal processing functions. Controller 109 may also generate various control signals to govern operations of the charged particle beam inspection system.

[0042] Condenser lens 210 is configured to focus primary electron beam 202. Condenser lens 210 may further be configured to adjust electric currents of primary beamlets 211, 212, and 213 downstream of source conversion unit 220 by varying the focusing power of condenser lens 210. Alternatively, the electric currents may be changed by altering the radial sizes of beam -limit apertures within the beam-limit aperture array corresponding to the individual primary beamlets. The electric currents may be changed by both altering the radial sizes of beam-limit apertures and the focusing power of condenser lens 210. Condenser lens 210 may be an adjustable condenser lens that may be configured so that the position of its first principal plane is movable. The adjustable condenser lens may be configured to be magnetic, which may result in off-axis beamlets 212 and 213 illuminating source conversion unit 220 with rotation angles. The rotation angles change with the focusing power or the position of the first principal plane of the adjustable condenser lens. Condenser lens 210 may be an anti-rotation condenser lens that may be configured to keep the rotation angles unchanged while the focusing power of condenser lens 210 is changed. In some embodiments, condenser lens 210 may be an adjustable anti-rotation condenser lens, in which the rotation angles do not change when its focusing power and the position of its first principal plane are varied.

[0043] Objective lens 231 may be configured to focus beamlets 211, 212, and 213 onto a sample 208 for inspection and may form, in the current embodiments, three probe spots 221, 222, and 223 on the surface of sample 208. Coulomb aperture plate 271, in operation, is configured to block off peripheral electrons of primary electron beam 202 to reduce Coulomb effect. The Coulomb effect may enlarge the size of each of probe spots 221, 222, and 223 of primary beamlets 211, 212, 213, and therefore deteriorate inspection resolution.

[0044] Beam separator 233 may, for example, be a Wien filter comprising an electrostatic deflector generating an electrostatic dipole field and a magnetic dipole field (not shown in Fig. 2A). Inoperation, beam separator 233 may be configured to exert an electrostatic force by electrostatic dipole field on individual electrons of primary beamlets 211, 212, and 213. The electrostatic force is equal in magnitude but opposite in direction to the magnetic force exerted by magnetic dipole field of beam separator 233 on the individual electrons. Primary beamlets 211, 212, and 213 may therefore pass at least substantially straight through beam separator 233 with at least substantially zero deflection angles.

[0045] Deflection scanning unit 232, in operation, is configured to deflect primary beamlets 211, 212, and 213 to scan probe spots 221, 222, and 223 across individual scanning areas in a section of the surface of sample 208. In response to incidence of primary beamlets 211, 212, and 213 or probe spots 221, 222, and 223 on sample 208, electrons emerge from sample 208 and generate three secondary electron beams 261, 262, and 263. Each of secondary electron beams 261, 262, and 263 typically comprise secondary electrons (having electron energy < 50eV) and backscattered electrons (having electron energy between 50eV and the landing energy of primary beamlets 211, 212, and 213). Beam separator 233 is configured to deflect secondary electron beams 261, 262, and 263 towards secondary projection system 250. Secondary projection system 250 subsequently focuses secondary electron beams 261, 262, and 263 onto detection elements 241, 242, and 243 of electron detection device 240. Detection elements 241, 242, and 243 are arranged to detect corresponding secondary electron beams 261, 262, and 263 and generate corresponding signals which are sent to controller 109 or a signal processing system (not shown), e.g., to construct images of the corresponding scanned areas of sample 208.

[0046] In some embodiments, detection elements 241, 242, and 243 detect corresponding secondary electron beams 261, 262, and 263, respectively, and generate corresponding intensity signal outputs (not shown) to an image processing system (e.g., controller 109). In some embodiments, each detection element 241, 242, and 243 may comprise one or more pixels. The intensity signal output of a detection element may be a sum of signals generated by all the pixels within the detection element.

[0047] In some embodiments, controller 109 may comprise image processing system that includes an image acquirer (not shown), a storage (not shown). The image acquirer may comprise one or more processors. For example, the image acquirer may comprise a computer, server, mainframe host, terminals, personal computer, any kind of mobile computing devices, and the like, or a combination thereof. The image acquirer may be communicatively coupled to electron detection device 240 of apparatus 104 through a medium such as an electrical conductor, optical fiber cable, portable storage media, IR, Bluetooth, internet, wireless network, wireless radio, among others, or a combination thereof. In some embodiments, the image acquirer may receive a signal from electron detection device 240 and may construct an image. The image acquirer may thus acquire images of sample 208. The image acquirer may also perform various post-processing functions, such as generating contours, superimposing indicators on an acquired image, and the like. The image acquirer may be configured to perform adjustments of brightness and contrast, etc. of acquired images. In some embodiments, thestorage may be a storage medium such as a hard disk, flash drive, cloud storage, random access memory (RAM), other types of computer readable memory, and the like. The storage may be coupled with the image acquirer and may be used for saving scanned raw image data as original images, and post-processed images.

[0048] In some embodiments, the image acquirer may acquire one or more images of a sample based on an imaging signal received from electron detection device 240. An imaging signal may correspond to a scanning operation for conducting charged particle imaging. An acquired image may be a single image comprising a plurality of imaging areas. The single image may be stored in the storage. The single image may be an original image that may be divided into a plurality of regions. Each of the regions may comprise one imaging area containing a feature of sample 208. The acquired images may comprise multiple images of a single imaging area of sample 208 sampled multiple times over a time sequence. The multiple images may be stored in the storage. In some embodiments, controller 109 may be configured to perform image processing steps with the multiple images of the same location of sample 208.

[0049] In some embodiments, controller 109 may include measurement circuitries (e.g., analog-to- digital converters) to obtain a distribution of the detected secondary electrons. The electron distribution data collected during a detection time window, in combination with corresponding scan path data of each of primary beamlets 211, 212, and 213 incident on the wafer surface, can be used to reconstruct images of the wafer structures under inspection. The reconstructed images can be used to reveal various features of the internal or external structures of sample 208, and thereby can be used to reveal any defects that may exist in the wafer.

[0050] In some embodiments, controller 109 may control motorized stage 209 to move sample 208 during inspection of sample 208. In some embodiments, controller 109 may enable motorized stage 209 to move sample 208 in a direction continuously at a constant speed. In other embodiments, controller 109 may enable motorized stage 209 to change the speed of the movement of sample 208 over time depending on the steps of scanning process.

[0051] Although Fig. 2A shows that apparatus 104 uses three primary electron beams, it is appreciated that apparatus 104 may use one, two, or more number of primary electron beams. The present disclosure does not limit the number of primary electron beams used in apparatus 104. In some embodiments, apparatus 104 may be a SEM used for lithography. In some embodiments, electron beam tool 104 may be a single-beam system or a multi-beam system.

[0052] For example, as shown in Fig. 2B, an electron beam tool 100B (also referred to herein as apparatus 100B) may be a single-beam inspection tool that is used in EBI system 100, consistent with embodiments of the present disclosure. Apparatus 100B includes a wafer holder 136 supported by motorized stage 134 to hold a wafer 150 to be inspected. Electron beam tool 100B includes an electron emitter, which may comprise a cathode 103, an anode 121, and a gun aperture 122. Electron beam tool 100B further includes a beam limit aperture 125, a condenser lens 126, a column aperture135, an objective lens assembly 132, and a detector 144. Objective lens assembly 132, in some embodiments, may be a modified SORIL lens, which includes a pole piece 132a, a control electrode 132b, a deflector 132c, and an exciting coil 132d. In an imaging process, an electron beam 161 emanating from the tip of cathode 103 may be accelerated by anode 121 voltage, pass through gun aperture 122, beam limit aperture 125, condenser lens 126, and be focused into a probe spot 170 by the modified SORIL lens and impinge onto the surface of wafer 150. Probe spot 170 may be scanned across the surface of wafer 150 by a deflector, such as deflector 132c or other deflectors in the SORIL lens. Secondary or scattered primary particles, such as secondary electrons or scattered primary electrons emanated from the wafer surface may be collected by detector 144 to determine intensity of the beam and so that an image of an area of interest on wafer 150 may be reconstructed.

[0053] There may also be provided an image processing system 199 that includes an image acquirer 120, a storage 130, and controller 109. Image acquirer 120 may comprise one or more processors. For example, image acquirer 120 may comprise a computer, server, mainframe host, terminals, personal computer, any kind of mobile computing devices, and the like, or a combination thereof. Image acquirer 120 may connect with detector 144 of electron beam tool 100B through a medium such as an electrical conductor, optical fiber cable, portable storage media, IR, Bluetooth, internet, wireless network, wireless radio, or a combination thereof. Image acquirer 120 may receive a signal from detector 144 and may construct an image. Image acquirer 120 may thus acquire images of wafer 150. Image acquirer 120 may also perform various post-processing functions, such as generating contours, superimposing indicators on an acquired image, and the like. Image acquirer 120 may be configured to perform adjustments of brightness and contrast, etc. of acquired images. Storage 130 may be a storage medium such as a hard disk, random access memory (RAM), cloud storage, other types of computer readable memory, and the like. Storage 130 may be coupled with image acquirer 120 and may be used for saving scanned raw image data as original images, and post-processed images. Image acquirer 120 and storage 130 may be connected to controller 109. In some embodiments, image acquirer 120, storage 130, and controller 109 may be integrated together as one electronic control unit.

[0054] In some embodiments, image acquirer 120 may acquire one or more images of a sample based on an imaging signal received from detector 144. An imaging signal may correspond to a scanning operation for conducting charged particle imaging. An acquired image may be a single image comprising a plurality of imaging areas that may contain various features of wafer 150. The single image may be stored in storage 130. Imaging may be performed on the basis of imaging frames.

[0055] The condenser and illumination optics of the electron beam tool may comprise or be supplemented by electromagnetic quadrupole electron lenses. For example, as shown in Fig. 2B, electron beam tool 100B may comprise a first quadrupole lens 148 and a second quadrupole lens 158. In some embodiments, the quadrupole lenses are used for controlling the electron beam. For example,first quadrupole lens 148 can be controlled to adjust the beam current and second quadrupole lens 158 can be controlled to adjust the beam spot size and beam shape.

[0056] Fig. 2B illustrates a charged particle beam apparatus in which an inspection system may use a single primary beam that may be configured to generate secondary electrons by interacting with wafer 150. Detector 144 may be placed along optical axis 105, as in the embodiment shown in Fig. 2B. The primary electron beam may be configured to travel along optical axis 105. Accordingly, detector 144 may include a hole at its center so that the primary electron beam may pass through to reach wafer 150.

[0057] Reference is now made to Fig. 3, which shows an example diagram of a charged particle source system 300. In some embodiments, charged particle source system 300 includes a high voltage module 310, cables 322, 324, 326, and 328, and charged particle source 330 (e.g., electron source). High voltage module 310 provides a high voltage and heating current to electron source 330 via cables 322 and 324 to heat filament 332. Each cable of cables 322, 324, 326, and 328 includes capacitance (e.g., stray capacitance).

[0058] Charged particle source 330 may be placed within a vacuum chamber and includes filament 332, electron source tip 334 (e.g., a Schottky tip, thermionic emitter, field emission emitter (e.g., Schottky emitter, cold field emitter), etc.), extractor 336, and anode 338. High voltage module 310 and charged particle source 330 are connected with high voltage cables 322, 324, 326, and 328, where each high voltage cable is shielded by shield conductors 322s, 324s, 326s, and 328s, respectively. Energy sources in charged particle source system 300 include, among others, high voltage module 310, the distributed capacitance of each high voltage cable (cables 322, 324, 326, and 328), and the distributed capacitance of different parts of charged particle source 330. Such energy sources may provide surge current into charged particle source 330 and filament 332, among other components, thereby causing high energy arcing in charged particle source 330 and damaging filament 332. For example, high energy arcing may occur when surfaces of metal electrodes in a vacuum begin to emit electrons either through heating (thermionic emission) or in an electric field that is sufficient to cause field electron emission, thereby resulting in overheating of or damage to components.

[0059] Reference is now made to Fig. 4, which shows an example diagram of a charged particle source system 400, consistent with embodiments of the present disclosure.

[0060] Charged particle source system 400 may include a high voltage module 410 (e.g., a high voltage source), cables 422, 424, 426, and 428, and charged particle source 430 (e.g., electron source, source 201 of Fig. 2A, source of electron beam tool 100B of Fig. 2B, etc.). In some embodiments, a high voltage source or high voltage module may be, for example, a source that generates a voltage sufficiently high to cause arcing in a vacuum chamber. Each cable of cables 422, 424, 426, and 428 may include a high voltage conductors 422c, 424c, 426c, and 428c, to conduct high voltage, and shield conductors 422s, 424s, 426s, and 428s, respectively, to shield the corresponding cable. High voltage module 410 provides a high voltage and heating current to charged particle source 430 viacables 422 and 424 to heat filament 432. Each cable of cables 422, 424, 426, and 428 includes capacitance (e.g., stray capacitance).

[0061] Charged particle source 430 is configured to operate in a vacuum environment (e.g., such as main chamber 101 of Fig. 1) and includes filament 432, electron source tip 434 (e.g., a Schottky tip, thermionic emitter, field emission emitter (e.g., Schottky emitter, cold field emitter), etc.), extractor 436, and anode 438. High voltage module 410 and charged particle source 430 are connected with high voltage cables 422, 424, 426, and 428, where each high voltage cable is shielded.

[0062] Cables 422, 424, 426, and 428 may be coupled between high voltage module 410 and charged particle source 430. A first component 441 (e.g., group of components) having an impedance may be at a first end of cables 422, 424, 426, and 428 (by high voltage module 410) while a second component 442 (e.g., group of components) having an impedance may be at a second end of cables 422, 424, 426, and 428 (by charged particle source 430). Charged particle source system 400 limits and reduces energy sources from outside of charged particle source 430 to protect the tip filament 432 and electron source tip 434. Components 441 provide an impedance to limit and reduce the energy source from stray capacitance in cables 422, 424, 426, and 428. For example, arcing may occur between a high voltage conductor (e.g., high voltage conductor 422c) of a cable and a shield conductor (e.g., shield conductor 426s) of another cable. In some embodiments, a component of components 441 (e.g., resistor 453) may limit current that may be provided by high voltage module 410, thereby reducing the arcing current. Components 442 provide an impedance to limit and reduce the energy source from high voltage module 410 and stray capacitance from cables 422, 424, 426, and 428. That is, components 441 and 442 having impedances may be configured to mitigate arcing energy provided to charged particle source 430.

[0063] Components 441 include components 451, 452, 453, and 454 (e.g., resistors, inductors, etc.), which are inserted into the cable wires 422, 424, 426, and 428 to reduce arcing energy from the high voltage module 410. Components 451, 452, 453, and 454 are inserted between a corresponding shield conductor 422s, 424s, 426s, and 428s and ground reference of each high voltage cable 422, 424, 426, and 428 to limit the peak current and energy from arcing, including for the channel to filament 432. That is, the components 441 having an impedance may be coupled between high voltage module 410 and a first end of the shield conductors 422s, 424s, 426s, and 428s of cables 422, 424, 426, and 428. Components 451, 452, 453, and 454 may be positioned at a first end of a corresponding cable of cables 422, 424, 426, and 428. For example, each component of components 451, 452, 453, and 454 may be coupled between the first end of a corresponding shield conductor 422s, 424s, 426s, and 428s and a ground reference. In some embodiments, any one of components 451, 452, 453, or 454 may be coupled between a node of high voltage module 410 and a first end of a corresponding shield conductor 422s, 424s, 426s, or 428s. In some embodiments, the node may be a high voltage output node of high voltage module 410. In some embodiments, the node may be a ground reference node.

[0064] Components 442 include components 461 and 462 (e.g., resistors, inductors, etc.), which are inserted into the cable wires 426 and 428, respectively, to reduce arcing energy from the cable capacitance to the channels to electron source tip 434 and extractor 436. In some embodiments, cable wires 422 and 424 may include inductances (e.g., small inductors) along with resistors (e.g., components 461 and 462). That is, components 442 having an impedance may be coupled between a second end of the shield conductors 422s, 424s, 426s, and 428s of cables 422, 424, 426, and 428 and charged particle source 430. Components 461 and 462 may be coupled between the second end of a shield conductor (shield conductors 426s and 428s) and charged particle source 430. Component 461 may be coupled to electron source tip 434 of charged particle source 430. Component 462 may be coupled to extractor 436.

[0065] Components 442 include components 463 and 464 (e.g., inductors, resistors, etc.) to limit peak current to filament 432. Since there can be 3A of current to fdament 432, components 463 and 464 may be inductors, rather than resistors, inserted into cable wires 422 and 424 to limit peak current. For example, components 463 and 464 may be coupled between the second end of a shield conductor (shield conductors 422s or 424s) and charged particle source 430. Components 463 and 464 may be coupled to fdament 432 of charged particle source 430.

[0066] Components 442 include a transient voltage suppressor (TVS) between fdament 432 and electron source tip 434 and a TVS between fdament 432 and extractor 436 to limit the maximum voltage when arcing occurs. Each of the TVSes include a diode (diodes 465 and 466, respectively) and a resistor (components 467 and 468, respectively) with a fast response protection function. For example, diodes 465 and 466 may be high-speed diodes and components 467 and 468 may be low- value resistors. Diode 465 and component 467 may be coupled in series between cables 424 and 426 while diode 466 and component 468 may be coupled in series between cables 426 and 428.

[0067] In some embodiments, charged particle source system 400 may reduce arcing energy from high voltage module 410 by 5-100 times and reduce arcing energy from more than 100 times at different arcing scenarios.

[0068] In some embodiments, components 442 may be in the vacuum environment of charged particle source 430.

[0069] Advantageously, charged particle source system 400 may limit and reduce the arcing energy to protect filament 432, including limiting the maximum voltage between filament 432 and electron source tip 434 and between filament 432 and extractor 436 to reduce the arcing energy. Additionally, charged particle source system 400 integrates impedance components 441 with the high voltage cables 422, 424, 426, and 428 and impedance components 442 near the charged particle source 430 high voltage feedthrough.

[0070] Advantageously, charged particle source system 400 may reduce damage to filament 432 caused by arcing outside of charged particle source 430. Additionally, charged particle source system 400 may increase manufacture yield, reduce manufacture cycle time, increase charged particle sourceproductivity, increase charged particle source reliability, increase charged particle source availability, increase charged particle system reliability, and increase charged particle system availability.

[0071] As stated previously, the disclosed embodiments may include a component having an impedance (e.g., a protection circuit) in cables coupled between a high voltage source (e.g., e-chuck box) and a wafer in a wafer holder (e.g., e-chuck). The component having an impedance may be coupled to one or more grounding pins configured to be coupled to the wafer of the wafer holder such that arcing energy provided to the wafer is mitigated. For example, high energy arcing may occur when an electric field that is sufficient to cause field electron emission arises between a metal surface of a component and a wafer, resulting in an arcing event between the surface and the wafer, thereby resulting in overheating of or damage to components (e.g., the wafer). In some embodiments, the component having an impedance may be coupled to clamping electrodes and a high voltage shielding ring that have capacitive couplings to the wafer. As a result, damage to the wafer in the wafer holder may be mitigated. Reference is now made to Fig. 5, which shows a diagram of a circuit 500 with an example protection circuit 510, consistent with embodiments of the present disclosure.

[0072] Protection circuit 510 may provide impedance (e.g., resistive or inductive, including resistors, inductors, capacitors, spark gaps, etc.) in one or more cables in series between an e-chuck box (e.g., a high voltage source) and one or more grounding pins in an e-chuck (e.g., wafer holder, sample holder 207 of Fig. 2A, wafer holder 136 of Fig. 2B, etc.) to avoid high currents through the wafer (e.g., sample 208 of Fig. 2A, wafer 150 of Fig. 2B, etc.). For example, each of a plurality of cables may have a corresponding protection circuit between the e-chuck box and a wafer (e.g., grounding pin of the wafer). Each cable may include a high voltage conductor to conduct high voltage and a shield conductor to shield the cable. The component having an impedance (protection circuit 510) may be configured to mitigate arcing energy provided to the e-chuck (and, consequently, the wafer).

[0073] In some embodiments, each grounding pin may be coupled to a corresponding protection circuit. In some embodiments, elements 521, 522, or 523 may be coupled to a single reference point (a single grounding pin) while in other embodiments elements 521, 522, or 523 may be coupled to different grounding pins. In some embodiments, a system may include a plurality of protection circuits in parallel where element 521 of the parallel protection circuits are coupled to a common point and elements 522 of some of the protection circuits are coupled to element 523 of a single protection circuit. It is understood that embodiments of the present disclosure are not limited to the above described configurations and that other configurations are possible. In some embodiments, protection circuit 510 may be positioned at the end of the cable near the grounding pin of the e-chuck to mitigate current from the cable flowing into a grounding pin.

[0074] In some embodiments, protection circuit 510 may include over-voltage protection 512 in the form of a gas discharge tube or a varistor or a TVS diode, which may be added in parallel to the load 532 towards an arbitrary reference.

[0075] Protection circuit 510 ensures that large amounts of current does not flow through the grounding pins to the surface metal layers on the wafer, thereby avoiding damage to the silicon of the wafer. Advantageously, protection circuit 510 may be provided at the end of coaxial cables between the e-chuck box and the grounding pins (where there is limited space) and may operate in vacuum conditions.

[0076] In some embodiments, the wafer may be coupled to one or more high capacitive components and an impedance (e.g., resistive or inductive, including resistors, inductors, capacitors, spark gaps, etc.) may be configured to be provided between the wafer and each of the one or more high capacitive components. In some embodiments, the impedance may include a protection circuit (e.g., resistive, inductive, over-voltage protection component 512, etc.).

[0077] Reference is now made to Fig. 6, which is a schematic diagram illustrating an exemplary electron beam inspection (EBI) system 600.

[0078] Electron beam inspection system may include electron beam tool 601.

[0079] EBI system 600 may include high voltage modules, such as high voltage wafer stage box (HWSB) 610 and high voltage wafer e-chuck box (HWEB) 620, which provide the necessary high voltage for high voltage components within a vacuum chamber of electron beam tool 601. For example, HWSB 610 may provide a high voltage to high voltage shielding plate (HVSP) 614 to adjust a landing energy of electron beams 690. HWSB 610 may provide a high voltage to No.5 plate 612 to adjust deflection of electron beams 690.

[0080] There are three main components in vacuum chamber 602: No.5 plate 612, HVSP 614, and components (e.g., mirror block 632, grounding pins 634 and 664, wafer clamping plates 636 and 638, ring plate 640, high voltage pins 666, 668, 670, sample plate 672) related to e-chuck 622. E-chuck 622 may hold wafer 674. The components related to e-chuck 622 may be coupled to HWEB 620 (e.g., coupled to e-chuck high voltage channel sharp pin 642 via high voltage cables 658, 676, 678, 680, 682, 684).

[0081] HWSB 610, HWEB 620, and high voltage components in vacuum chamber 602 may be connected to other components in electron beam tool 600 via long high voltage cables, where each high voltage cable may be shielded (e.g., each cable may include a high voltage conductor to conduct high voltage and a shield conductor to shield the cable). For example, HWSB 610 may be connected to No.5 plate 612 by high voltage cable 652, HWSB 610 may be connected to HVSP 614 by high voltage cable 654, HWSB may be connected to HWEB 620 by high voltage cable 656, and HWEB 620 may be connected to mirror block 632 or components on or near e-chuck 622 by high voltage cables 658, 676, 678, 680, 682, or 684 (e.g., sharp pin 642 may be connected to mirror block 632, e- chuck 622, plates 636, 638, 672, ring 640, pins 664, 666, 668, 670, 634 by high voltage cables 658, 676, 678, 680, 682, 684). Mirror block 632 may be used to measure the wafer position accurately with a laser interferometer integrated in electron beam tool 601. Mirror block 632 may be part of a wafer stage.

[0082] Arcing energy sources may include HWSB 610, HWEB 620, the distributed capacitance of the long high voltage cables (e.g., cables 652, 654, 656, 658, 676, 678, 680, 682, 684), or the distributed capacitance of different high voltage components in vacuum chamber 602. Theses arcing energy sources provide surge current into the high voltage components of vacuum chamber 602 such that the arcing energy is large. Since these arcing energy sources are on different high voltage channels, they may cause secondary arcing between the different components, including at critical positions in EBI system 600 (e.g., on mirror block 632 to HVSP 614 or grouping pins to HSVP 614). Primary arcing may refer to arcing that occurs directly from high voltage sources, such as high voltage modules and high voltage cables. Secondary arcing may refer to arcing that occurs indirectly from high voltage sources (e.g., secondary arcing between No.5 plate 612 and HVSP 614 occurs as a result of primary arcing from high voltage modules 610 or 620 or high voltage cables). Secondary arcing may cause critical damage to electron beam tool 601. These arcing energy source cause damage to the components in EBI system 600, including the coating of mirror block 632 and wafer 674. A mirror block is attached to a stage and is used in a laser interferometer system to accurately control the position of the stage. Damage to the coating may affect the accuracy of stage movement and positioning.

[0083] Reference is now made to Fig. 7, which is a schematic diagram illustrating an exemplary electron beam inspection (EBI) system 700 (e.g., EBI system 100 of Fig. 1, charged particle source system 400, circuit 500 of Fig. 5), consistent with embodiments of the present disclosure.

[0084] In some embodiments, electron beam inspection system may include electron beam tool 701 (e.g., electron beam tool 104 of Fig. 1, electron beam tool 104 of Fig. 2A, electron beam tool 100B of Fig. 2B)

[0085] EBI system 700 may include high voltage modules, such as high voltage wafer stage box (HWSB) 710 and high voltage wafer e-chuck box (HWEB) 720, which provide the necessary high voltage for high voltage components within a vacuum chamber of electron beam tool 701. For example, HWSB 710 may provide a high voltage to high voltage shielding plate (HVSP) 714 to adjust a landing energy of electron beams 790 (charged particle beams). HWSB 710 may provide a high voltage to No.5 plate 712 to adjust deflection of electron beams 790.

[0086] There are three main components in vacuum chamber 702: No.5 plate 712, HVSP 714, and components (e.g., mirror block 732, grounding pins 734 and 764, wafer clamping plates 736 and 738, ring plate 740, high voltage pins 766, 768, 770, sample plate 772) related to e-chuck 722 (e.g., wafer holder, sample holder 207 of Fig. 2A, wafer holder 136 of Fig. 2B, etc.). E-chuck 722 may hold wafer 774 (e.g., sample 208 of Fig. 2A, wafer 150 of Fig. 2B). The components related to e-chuck 722 may be coupled to HWEB 720 (e.g., coupled to e-chuck high voltage channel sharp pin 742 via high voltage cables 758, 776, 778, 780, 782, 784).

[0087] HWSB 710, HWEB 720, and high voltage components in vacuum chamber 702 may be connected to other components in electron beam tool 700 via long high voltage cables, where eachhigh voltage cable may be shielded (e.g., each cable may include a high voltage conductor to conduct high voltage and a shield conductor to shield the cable). For example, HWSB 710 may be connected to No.5 plate 712 by high voltage cable 752, HWSB 710 may be connected to HVSP 714 by high voltage cable 754, HWSB may be connected to HWEB 720 by high voltage cable 756, and HWEB 720 may be connected to mirror block 732 or components on or near e-chuck 722 by high voltage cables 758, 776, 778, 780, 782, or 784 (e.g., sharp pin 742 may be connected to mirror block 732, e- chuck 722, plates 736, 738, 772, ring 740, pins 764, 766, 768, 770, 734 by high voltage cables 758, 776, 778, 780, 782, 784). Mirror block 732 may be used to measure the wafer position accurately with a laser interferometer integrated in electron beam tool 701. In some embodiments, mirror block 732 may be part of a wafer stage (e.g., motorized stage 209 of Fig. 2A, motorized stage 134 of Fig. 2B).

[0088] Arcing energy sources may include HWSB 710, HWEB 720, the distributed capacitance of the long high voltage cables (e.g., cables 752, 754, 756, 758, 776, 778, 780, 782, 784), or the distributed capacitance of different high voltage components in vacuum chamber 702. In some embodiments, EBI system 700 may limit and reduce arcing energy from these high voltage sources by providing an impedance.

[0089] In some embodiments, components 786 providing the impedance may include resistors of varying sizes, inductors of varying sizes, or transient voltage suppressors (TVS) (e.g., one or more diodes with fast response protection function). In some embodiments, the components providing an impedance may limit the voltage gap between No.5 plate 712 and HVSP 714, thereby reducing secondary arcing (e.g., arcing that occurs between No.5 plate 712 and HVSP 714). In some embodiments, this secondary arcing may be triggered by the voltage gap between No.5 plate 712 and HVSP 714. When this voltage gap is limited, arcing will not occur. In some embodiments, primary arcing may refer to arcing that occurs directly from high voltage sources, such as high voltage modules and high voltage cables. In some embodiments, secondary arcing may refer to arcing that occurs indirectly from high voltage sources (e.g., secondary arcing between No.5 plate 712 and HVSP 714 occurs as a result of primary arcing from high voltage modules 710 or 720 or high voltage cables). Secondary arcing may cause critical damage to electron beam tool 701.

[0090] In some embodiments, components 786 providing an impedance include larger value resistors or inductors (e.g., 700R1, 700R2, 700R3), which are inserted into cables or channels coupled to No.5 plate 712, HVSP 714, or sharp pin 742 of HWEB 720 to block arcing energy from the high voltage modules (e.g., HWSB 710, HWEB 720) and from high voltage cable capacitance (e.g., capacitance from high voltage cables 752, 754, 756, 758, 776, 778, 780, 782, 784).

[0091] In some embodiments, components 786 providing an impedance include TVSes (e.g., 700D1, 700D2, 701D, 702D, 703D, 704D, 705D), which are inserted into cables or channels coupled to No.5 plate 712, HVSP 714, or sharp pin 742 of HWEB 720 to limit or reduce the maximum voltage when arcing occurs.

[0092] In some embodiments, components 786 providing an impedance include smaller value resistors or inductors (e.g., 701R, 702R, 703R, 704R, 705R), which are inserted into cables 784, 782, 780, 778, 776 (e.g., output channels from HWEB 720 to plates 736, 738, and 772, pins 764, 766, 768, 770, and 734, ring 740) to limit peak current through these cables, thereby reducing arcing energy from the high voltage modules (e.g., HWSB 710, HWEB 720) and from high voltage cable capacitance (e.g., capacitance from high voltage cables 752, 754, 756, 758, 776, 778, 780, 782, 784).

[0093] In some embodiments, components 786 providing an impedance include one or more TVSes (e.g., 700D2, 701D, 702D, 703D, 704D, 705D) in the output channels from HWEB 720 to limit the maximum voltage when arcing occurs. These TVSes avoid secondary arcing from components on or near e-chuck 722 (e.g., plates 736, 738, and 772, pins 764, 766, 768, 770, and 734, ring 740, mirror block 732) to HVSP 714, thereby ensuring there is no damage to components in EBI system 700. In some embodiments, TVSes may ensure smaller value resistors (e.g., 701R, 702R, 703R, 704R, 705R) work well to limit the arcing energy, since the TVSes may maintain the same voltage as sharp pin 742 and channels coupled to HVSP 714. In some embodiments, the TVSes may sink high amounts of energy and clamp the peak voltage where they are assembled such that they block secondary arcing.

[0094] In some embodiments, EBI system 700 may include an electrical coupling mechanism that is coupled to electron beam tool 701. The electrical coupling mechanism may include the high voltage cables and components 786.

[0095] While some components have been described above as “larger value” or “smaller value” (e.g., with respect to resistors or inductors), it is understood that embodiments of the present disclosure encompass configurations where components described as “larger value” may be “smaller value” and components described as “smaller value” may be “larger value.”

[0096] A non-transitory computer readable medium may be provided that stores instructions for a processor of a controller (e.g., controller 109 of Fig. 1) for controlling the electron beam tool or other systems of other systems and servers, or components thereof, consistent with embodiments in the present disclosure. These instructions may allow the one or more processors to carry out image processing, data processing, beamlet scanning, graphical display, operations of a charged particle beam apparatus, or another imaging device, or the like. Common forms of non-transitory media include, for example, a floppy disk, a flexible disk, hard disk, solid state drive, magnetic tape, or any other magnetic data storage medium, a Compact Disc Read Only Memory (CD-ROM), any other optical data storage medium, any physical medium with patterns of holes, a Random Access Memory (RAM), a Programmable Read Only Memory (PROM), and Erasable Programmable Read Only Memory (EPROM), a FLASH-EPROM or any other flash memory, Non-Volatile Random Access Memory (NVRAM), a cache, a register, any other memory chip or cartridge, and networked versions of the same.

[0097] The embodiments may further be described using the following clauses:1. An assembly for reducing arcing energy in a charged particle system, comprising:a plurality of cables coupled between a high voltage source and a charged particle source; a first component providing impedance at first ends of the plurality of cables; and a second component providing impedance at second ends of the plurality of cables, wherein the first component and the second component are configured to mitigate arcing energy provided to the charged particle source.2. The assembly of clause 1, wherein each cable of the plurality of cables comprises a high voltage conductor to conduct high voltage and a shield conductor to shield the cable.3. The assembly of clause 2, wherein the first component is coupled between a node of the high voltage source and first ends of the shield conductors of the plurality of cables.4. The assembly of clause 3, wherein the node is a high voltage output node.5. The assembly of clause 3, wherein the node is a ground reference node.6. The assembly of any one of clauses 2-5, wherein the second component is coupled between second ends of the shield conductors of the plurality of cables and the charged particle source.7. The assembly of any one of clauses 1-6, wherein the first component comprises a plurality of resistors.8. The assembly of clause 7, wherein each resistor of the plurality of resistors is positioned at the first end of a corresponding cable of the plurality of cables.9. The assembly of any one of clauses 7-8, wherein each resistor of the plurality of resistors is coupled between the first end of a corresponding shield conductor and a ground reference.10. The assembly of any one of clauses 6-9, wherein the second component comprises at least one inductor between the second end of a shield conductor and the charged particle source.11. The assembly of clause 10, wherein the second component comprises at least one resistor between the at least one inductor and the charged particle source.12. The assembly of any one of clauses 10-11, wherein the at least one inductor is coupled to a filament of the charged particle source.13. The assembly of any one of clauses 6-12, wherein the second component comprises at least one resistor between the second end of a shield inductor and the charged particle source.14. The assembly of clause 13, wherein the at least one resistor is coupled to an electron source tip of the charged particle source.15. The assembly of any one of clauses 13-14, wherein the at least one resistor is coupled to an extractor of the charged particle source.16. The assembly of any one of clauses 2-12, wherein the second component comprises at least one high-speed diode and at least one low-value resistor coupled in series between at least one pair of high voltage conductors of the plurality of cables.17. An assembly for reducing arcing energy in a charged particle system, comprising: a cable configured to be coupled between a high voltage source and a wafer; anda component comprising an impedance in the cable, the component comprising the impedance configured to be coupled to the wafer, wherein the component comprising the impedance is configured to mitigate arcing energy provided to the wafer.18. The assembly of clause 17, wherein the cable comprises a high voltage conductor to conduct high voltage and a shield conductor to shield the cable.19. The assembly of any one of clauses 17-18, wherein the component comprising an impedance comprises a protection circuit.20. The assembly of clause 19, wherein the protection circuit is a resistor or an inductor.21. The assembly of clause 19, wherein the protection circuit comprises an over-voltage protection component.22. The assembly of any one of clauses 17-21, wherein the component comprising the impedance is configured to be positioned at an end of the cable by the wafer.23. The assembly of any one of clauses 19-22, wherein the protection circuit comprises a plurality of protection circuits.24. The assembly of any one of clauses 17-23, further comprising a plurality of grounding pins configured to be coupled to the wafer.25. The assembly of clause 24, wherein each grounding pin is coupled to a corresponding protection circuit.26. The assembly of any one of clauses 17-25, further comprising one or more high capacitive components configured to be coupled to the wafer.27. The assembly of clause 26, further comprising a component comprising an impedance configured to be between the wafer and each of the one or more high capacitive components.28. The assembly of clause 27, wherein the component comprising the impedance comprises a protection circuit.29. The assembly of clause 28, wherein the protection circuit is a resistor or an inductor.30. The assembly of clause 28, wherein the protection circuit comprises an over-voltage protection component.31. An assembly for reducing arcing energy in a charged particle system, comprising: a first component comprising an impedance coupled with a high voltage source and a first end of a plurality of cables; and a second component comprising an impedance coupled with a second end of the plurality of cables and a charged particle source, wherein the first component and the second component are configured to mitigate damage to the charged particle source.32. The assembly of clause 31, wherein each cable of the plurality of cables comprises a high voltage conductor to conduct high voltage and a shield conductor to shield the cable.33. The assembly of clause 32, wherein the first component is coupled between a node of the high voltage source and first ends of the shield conductors of the plurality of cables.34. The assembly of clause 33, wherein the node is a high voltage output node.35. The assembly of clause 33, wherein the node is a ground reference node.36. The assembly of any one of clauses 32-35, wherein the second component is coupled between second ends of the shield conductors of the plurality of cables and the charged particle source.37. The assembly of any one of clauses 31-36, wherein the first component comprises a plurality of resistors.38. The assembly of clause 37, wherein each resistor of the plurality of resistors is positioned at the first end of a corresponding cable of the plurality of cables.39. The assembly of any one of clauses 37-38, wherein each resistor of the plurality of resistors is coupled between the first end of a corresponding shield conductor and a ground reference.40. The assembly of any one of clauses 36-39, wherein the second component comprises at least one inductor between the second end of a shield conductor and the charged particle source.41. The assembly of clause 40, wherein the second component comprises at least one resistor between the at least one inductor and the charged particle source.42. The assembly of any one of clauses 40-41, wherein the at least one inductor is coupled to a filament of the charged particle source.43. The assembly of any one of clauses 36-42, wherein the second component comprises at least one resistor between the second end of a shield inductor and the charged particle source.44. The assembly of clause 43, wherein the at least one resistor is coupled to an electron source tip of the charged particle source.45. The assembly of any one of clauses 43-44, wherein the at least one resistor is coupled to an extractor of the charged particle source.46. The assembly of any one of clauses 32-42, wherein the second component comprises at least one high-speed diode and at least one low-value resistor coupled in series between at least one pair of high voltage conductors of the plurality of cables.47. An assembly for reducing arcing energy in a charged particle system, comprising: a component comprising an impedance configured to be coupled to a cable and a wafer, wherein the component is configured to mitigate damage to the wafer.48. The assembly of clause 47, wherein the cable comprises a high voltage conductor to conduct high voltage and a shield conductor to shield the cable.49. The assembly of any one of clauses 47-48, wherein the component comprising an impedance comprises a protection circuit.50. The assembly of clause 49, wherein the protection circuit is a resistor or an inductor.51. The assembly of clause 49, wherein the protection circuit comprises an over-voltage protection component.52. The assembly of any one of clauses 47-51, wherein the component comprising the impedance is configured to be positioned at an end of the cable by the wafer.53. The assembly of any one of clauses 49-52, wherein the protection circuit comprises a plurality of protection circuits.54. The assembly of any one of clauses 47-53, further comprising a plurality of grounding pins configured to be coupled to the wafer.55. The assembly of clause 54, wherein each grounding pin is coupled to a corresponding protection circuit.56. The assembly of any one of clauses 47-55, further comprising one or more high capacitive components configured to be coupled to the wafer.57. The assembly of clause 56, further comprising a component comprising an impedance configured to be between the wafer and each of the one or more high capacitive components.58. The assembly of clause 57, wherein the component comprising the impedance comprises a protection circuit.59. The assembly of clause 58, wherein the protection circuit is a resistor or an inductor.60. The assembly of clause 58, wherein the protection circuit comprises an over-voltage protection component.61. An assembly for reducing arcing energy in a charged particle system, comprising: an electrical coupling mechanism configured to couple a high voltage source to a charged particle tool, the electrical coupling mechanism comprising: a cable from the high voltage source, and an impedance component coupled to the charged particle tool and configured to mitigate arcing energy provided by any one of the cable or the high voltage source to the charged particle tool.62. The assembly of clause 61, wherein the cable comprises a high voltage conductor to conduct high voltage and a shield conductor to shield the cable.63. The assembly of any one of clauses 61-62, wherein the impedance component is coupled between the high voltage source and a first plate configured to adjust a landing energy of charged particle beams in the charged particle tool.64. The assembly of any one of clauses 61-63, wherein the impedance component is coupled between the high voltage source and a second plate configured to adjust deflection of charged particle beams in the charged particle tool.65. The assembly of any one of clauses 63-64, wherein the impedance component is configured to limit a voltage gap between the first plate and the second plate.66. The assembly of clause 65, wherein a source of the arcing energy is the voltage gap between the first plate and the second plate.67. The assembly of any one of clauses 61-66, wherein a source of the arcing energy is the cable.68. The assembly of any one of clauses 61-67, wherein a source of the arcing energy is the high voltage source.69. The assembly of any one of clauses 61-68, wherein the impedance component is coupled between the high voltage source and a wafer of the charged particle tool.70. The assembly of clause 69, wherein the impedance component is coupled between the high voltage source and a wafer stage of the charged particle tool.71. The assembly of any one of clauses 61-70, wherein the impedance component comprises any one of a resistor, an inductor, or a transient voltage suppressor (TVS).72. The assembly of clause 71, wherein the TVS comprises one or more diodes.73. An assembly for reducing arcing energy in a charged particle system, comprising: an electrical coupling mechanism configured to couple to a charged particle tool, the electrical coupling mechanism comprising: a cable, and an impedance component coupled to the cable and to the charged particle tool wherein the impedance component is configured to mitigate damage to the charged particle tool.74. The assembly of clause 73, wherein the cable comprises a high voltage conductor to conduct high voltage and a shield conductor to shield the cable.75. The assembly of any one of clauses 73-74, wherein the impedance component is coupled between a high voltage source and a first plate configured to adjust a landing energy of charged particle beams in the charged particle tool.76. The assembly of any one of clauses 73-75, wherein the impedance component is coupled between a high voltage source and a second plate configured to adjust deflection of charged particle beams in the charged particle tool.77. The assembly of any one of clauses 75-76, wherein the impedance component is configured to limit a voltage gap between the first plate and the second plate.78. The assembly of clause 77, wherein a source of the arcing energy is the voltage gap between the first plate and the second plate.79. The assembly of any one of clauses 73-78, wherein a source of the arcing energy is the cable.80. The assembly of any one of clauses 73-79, wherein a source of the arcing energy is a high voltage source.81. The assembly of any one of clauses 73-80, wherein the impedance component is coupled between a high voltage source and a wafer of the charged particle tool.82. The assembly of clause 81, wherein the impedance component is coupled between the high voltage source and a wafer stage of the charged particle tool.83. The assembly of any one of clauses 73-82, wherein the impedance component comprises any one of a resistor, an inductor, or a transient voltage suppressor (TVS).84. The assembly of clause 83, wherein the TVS comprises one or more diodes.

[0098] It will be appreciated that the embodiments of the present disclosure are not limited to the exact construction that has been described above and illustrated in the accompanying drawings, and that various modifications and changes may be made without departing from the scope thereof.

Claims

CLAIMS1. An assembly for reducing arcing energy in a charged particle system, comprising: a plurality of cables coupled between a high voltage source and a charged particle source; a first component providing impedance at first ends of the plurality of cables; and a second component providing impedance at second ends of the plurality of cables, wherein the first component and the second component are configured to mitigate arcing energy provided to the charged particle source.

2. The assembly of claim 1, wherein each cable of the plurality of cables comprises a high voltage conductor to conduct high voltage and a shield conductor to shield the cable.

3. The assembly of claim 2, wherein the first component is coupled between a node of the high voltage source and first ends of the shield conductors of the plurality of cables.

4. The assembly of claim 3, wherein the node is a high voltage output node.

5. The assembly of claim 3, wherein the node is a ground reference node.

6. The assembly of claim 2, wherein the second component is coupled between second ends of the shield conductors of the plurality of cables and the charged particle source.

7. The assembly of claim 1, wherein the first component comprises a plurality of resistors.

8. The assembly of claim 7, wherein each resistor of the plurality of resistors is positioned at the first end of a corresponding cable of the plurality of cables.

9. The assembly of claim 7, wherein each resistor of the plurality of resistors is coupled between the first end of a corresponding shield conductor and a ground reference.

10. The assembly of claim 6, wherein the second component comprises at least one inductor between the second end of a shield conductor and the charged particle source.

11. The assembly of claim 10, wherein the second component comprises at least one resistor between the at least one inductor and the charged particle source.

12. The assembly of claim 10, wherein the at least one inductor is coupled to a fdament of the charged particle source.

13. The assembly of claim 6, wherein the second component comprises at least one resistor between the second end of a shield inductor and the charged particle source.

14. The assembly of claim 2, wherein the second component comprises at least one high-speed diode and at least one low-value resistor coupled in series between at least one pair of high voltage conductors of the plurality of cables.

15. An assembly for reducing arcing energy in a charged particle system, comprising: a cable configured to be coupled between a high voltage source and a wafer; and a component comprising an impedance in the cable, the component comprising the impedance configured to be coupled to the wafer, wherein the component comprising the impedance is configured to mitigate arcing energy provided to the wafer.

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