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1 APPARATUS AND METHOD FIELD [0001] The embodiments provided herein generally relate to charged particle optical devices and 5 methods of projecting charged particles, and particularly to devices and methods that use multiple beams of charged particles. BACKGROUND [0002] When manufacturing semiconductor integrated circuit (IC) chips, undesired pattern defects, 10 as a consequence of, for example, optical effects and incidental particles, inevitably occur on a substrate (i.e. wafer) or a mask during the fabrication processes, thereby reducing the yield. Monitoring the extent of the undesired pattern defects is therefore an important process in the manufacture of IC chips. More generally, the inspection and/or measurement of a surface of a substrate, or other object/material, is an important process during and/or after its manufacture. 15 [0003] Pattern inspection tools with a charged particle beam have been used to inspect objects, for example to detect pattern defects. These tools typically use electron microscopy techniques, such as a scanning electron microscope (SEM). In a SEM, a primary electron beam of electrons at a relatively high energy is targeted with a final deceleration step in order to land on a sample at a relatively low landing energy. The beam of electrons is focused as a probing spot on the sample. The interactions 20 between the material structure at the probing spot and the landing electrons from the beam of electrons cause signal charged particles to be emitted from the surface, such as secondary electrons, backscattered electrons or Auger electrons. The generated secondary electrons may be emitted from the material structure of the sample. By scanning the primary electron beam as the probing spot over the sample surface, signal charged particles can be emitted across the surface of the sample. By 25 collecting these emitted signal charged particles from the sample surface, a pattern inspection tool may obtain data relating to the material structure of the surface of the sample, e.g. which may be used to form an image representing characteristics of the material structure of the sample surface. [0004] There is a general need to improve the throughput and other characteristics of charged particle optical devices. In particular, it is desirable to be able to control the landing energy of the electrons 30 incident on the sample in a convenient manner. SUMMARY [0005] It is an object of the present disclosure to provide embodiments that support improvement of throughput or other characteristics of charged particle optical devices. 35 Confidential 2 BRIEF DESCRIPTION OF FIGURES [0006] The above and other embodiments of the present disclosure will become more apparent from the description of exemplary embodiments, taken in conjunction with the accompanying drawings. [0007] FIG. 1 is a schematic diagram illustrating an exemplary charged particle beam inspection 5 apparatus. [0008] FIG. 2 is a schematic diagram illustrating an exemplary multi-beam apparatus that is part of the exemplary charged particle beam inspection apparatus of FIG. 1 . [0009] FIG. 3 is a schematic diagram of an exemplary multi-beam apparatus according to an embodiment. 10 [0010] FIG. 4 is a graph of landing energy vs. resolution of an exemplary arrangement. [0011] FIG. 5 is an enlarged diagram of a control lens and an objective lens according to an embodiment. [0012] FIG. 6 is a schematic cross-sectional view of an objective lens according to an embodiment. [0013] FIG. 7A and FIG. 7B are schematic cross-sectional views of an objective lens according to 15 embodiments. [0014] FIG. 8 is a schematic cross-sectional view of portions of electrodes forming objective lenses with a final beam-limiting aperture array according to an embodiment. [0015] FIG. 9 is a schematic magnified top sectional view relative to plane A-A in FIG. 8 showing an aperture in the final beam-limiting aperture array 20 [0016] FIG. 10 is a schematic diagram of an exemplary charged particle system according to an embodiment comprising a macro collimator and macro scan deflector. [0017] FIG. 11 is a schematic diagram of an exemplary charged particle system according to an embodiment comprising a collimator element array and a scan-deflector array. [0018] The schematic diagrams and views show the components described below. However, the 25 components depicted in the figures are not to scale. 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 30 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 invention. Instead, they are merely examples of devices and methods consistent with the invention as disclosed herein. [0020] The enhanced computing power of electronic devices, which reduces the physical size of the 35 devices, can be accomplished by significantly increasing the packing density of circuit components such as transistors, capacitors, diodes, etc. on an IC chip. This has been enabled by increased resolution enabling yet smaller structures to be made. For example, an IC chip of a smart phone, Confidential 3 which is the size of a thumbnail and available in, or earlier than, 2019, may include over 2 billion transistors, the size of each transistor being less than 1/1000th of a human hair. Thus, it is not surprising that semiconductor IC manufacturing is a complex and time-consuming process, with hundreds of individual steps. Errors in even one step have the potential to dramatically affect the 5 functioning of the final product. Just one “killer defect” can cause device failure. The goal of the manufacturing process is to improve the overall yield of the process. For example, to obtain a 75% yield for a 50-step process (where a step can indicate the number of layers formed on a wafer), each individual step must have a yield greater than 99.4%,. If each individual step had a yield of 95%, the overall process yield would be as low as 7%. 10 [0021] While high process yield is desirable in an IC chip manufacturing facility, maintaining a high substrate (i.e. wafer) throughput, defined as the number of substrates processed per hour, is also essential. High process yield and high substrate throughput can be impacted by the presence of a defect. This is especially true if operator intervention is required for reviewing the defects. Thus, high throughput detection and identification of micro and nano-scale defects by inspection tools (such 15 as a Scanning Electron Microscope (‘SEM’)) is essential for maintaining high yield and low cost. [0022] A SEM comprises a scanning device and a detector apparatus. The scanning device comprises an illumination apparatus that comprises an electron source, for generating primary electrons, and a projection apparatus for scanning a sample, such as a substrate, with one or more focused beams of primary electrons. Together at least the illumination apparatus, or illumination 20 system, and the projection apparatus, or projection system, may be referred to together as the electron- optical system or apparatus. The primary electrons interact with the sample and generate secondary electrons. The detection apparatus captures the secondary electrons from the sample as the sample is scanned so that the SEM can obtain data of the scanned area of the sample, which may for example, be used to create an image of the scanned area of the sample. For high throughput inspection, some of 25 the inspection apparatuses use multiple focused beams of primary electrons, i.e. a multi-beam. The component beams of the multi-beam may be referred to interchangeably as beams, sub-beams or beamlets. A multi-beam can scan different parts of a sample simultaneously. A multi-beam inspection apparatus can therefore inspect a sample at a much higher speed than a single-beam inspection apparatus. 30 [0023] An implementation of a known multi-beam inspection apparatus is described below. [0024] The figures are schematic. Relative dimensions of components in drawings are therefore 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. While the description and drawings are directed to an 35 electron-optical apparatus, it is appreciated that the embodiments are not used to limit the present disclosure to specific charged particles. References to electrons throughout the present document may Confidential 4 therefore be more generally be considered to be references to charged particles, with the charged particles not necessarily being electrons. [0025] Reference is now made to FIG. 1 , which is a schematic diagram illustrating an exemplary charged particle beam inspection apparatus 100. The charged particle beam inspection apparatus 100 5 is an example of a charged particle system. The charged particle beam inspection apparatus 100 of FIG. 1 includes a main chamber 10, a load lock chamber 20, an electron beam tool 40, an equipment front end module (EFEM) 30 and a controller 50. Electron beam tool 40 is located within main chamber 10. [0026] EFEM 30 includes a first loading port 30a and a second loading port 30b. EFEM 30 may 10 include additional loading port(s). First loading port 30a and second loading port 30b may, for example, receive substrate front opening unified pods (FOUPs) that contain substrates (e.g., semiconductor substrates or substrates made of other material(s)) or samples to be inspected (substrates, wafers and samples are collectively referred to as “samples” hereafter). One or more robot arms (not shown) in EFEM 30 transport the samples to load lock chamber 20. 15 [0027] Load lock chamber 20 is used to remove the gas around a sample. This creates a vacuum that is a local gas pressure lower than the pressure in the surrounding environment. The load lock chamber 20 may be connected to a load lock vacuum pump system (not shown), which removes gas particles in the load lock chamber 20. The operation of the load lock vacuum pump system enables the load lock chamber to reach a first pressure below the atmospheric pressure. After reaching the 20 first pressure, one or more robot arms (not shown) transport the sample from load lock chamber 20 to main chamber 10. Main chamber 10 is connected to a main chamber vacuum pump system (not shown). The main chamber vacuum pump system removes gas particles in main chamber 10 so that the pressure around the sample reaches a second pressure lower than the first pressure. After reaching the second pressure, the sample is transported to the electron beam tool 40 by which it may be 25 inspected. An electron beam tool 40 may comprise a charged particle optical device as described below, e.g. multi-beam electron-optical apparatus. [0028] Controller 50 is electronically connected to electron beam tool 40. Controller 50 may be a processor (such as a computer) configured to control the charged particle beam inspection apparatus 100. Controller 50 may also include a processing circuitry configured to execute various signal 30 and/or image processing functions. While controller 50 is shown in FIG. 1 as being outside of the structure that includes main chamber 10, load lock chamber 20, and EFEM 30, it is appreciated that controller 50 may be part of the structure. The controller 50 may be located in one of the component elements of the charged particle beam inspection apparatus or it can be distributed over at least two of the component elements. While the present disclosure provides examples of main chamber 10 35 housing an electron beam inspection tool, it should be noted that aspects of the disclosure in their broadest sense are not limited to a chamber housing an electron beam inspection tool. Rather, it is Confidential ...