Charged particle device

Abstract

A charged particle apparatus for projecting a charged particle beam of a plurality of beam grids toward a plurality of samples is provided. The apparatus includes: a stage configured to support a plurality of samples at respective sample locations; and an array of charged particle devices, each configured to project the plurality of charged particle beams in the beam grid to respective sample locations. The charged particle devices each include an array of objective lenses configured to direct respective light beams of a beam grid of the charged particle devices onto a sample at respective sample locations and a detector configured to detect signal particles from the sample. The stage is configured to be actuated relative to the array of charged particle devices. The stage and the array of charged particle devices are configured such that the array of charged particle devices scans simultaneously relative to the plurality of samples.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to EP application 22198397.6 filed on September 28, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Embodiments provided herein generally relate to charged particle devices. Background Art

[0004] When manufacturing semiconductor integrated circuit (IC) chips, undesirable pattern defects on the substrate (i.e., wafer) or mask are inevitably present during the manufacturing process due to optical effects and accidental particles, thereby reducing the yield. Therefore, monitoring the extent of undesirable pattern defects is an important process in IC chip manufacturing. More generally, evaluating (e.g., inspecting and / or measuring) the surface of a substrate or other object / material is an important process during and / or after manufacturing.

[0005] Pattern evaluation systems of charged particle beams have been used to inspect objects, such as detecting pattern defects and measuring structural features on such objects. These tools typically use electron microscopy techniques, using electron optical systems, such as scanning electron microscopes (SEMs). In an exemplary electron optical system (such as a SEM), a relatively high-energy electron beam is targeted and a final deceleration step is performed so that it lands on a sample with a relatively low landing energy. The electron beam is focused on a probe point on the sample. The interaction between the material structure at the probe point and the landing electrons of the electron beam causes electrons to be emitted from the surface, such as secondary electrons, backscattered electrons, or Auger electrons. The secondary electrons generated can be emitted from the material structure of the sample. By scanning the sample surface with the primary electron beam as a probe point, secondary electrons can be emitted on the entire sample surface. By collecting these secondary electrons emitted from the sample surface, a pattern evaluation system (or evaluation tool) can obtain an image representing the material structural features of the sample surface. The intensity of the electron beam composed of backscattered electrons and secondary electrons can vary according to the characteristics of the internal and external structures of the sample, thereby indicating whether the sample has defects.

[0006] It is desirable to increase the throughput of an evaluation system, for example for inspection, so that samples can be processed more quickly. Specifically, it is desirable to increase the throughput to one wafer per hour. One technique for increasing the throughput of an evaluation system is to increase the number of charged particle devices (also referred to as columns) that are positioned to scan each sample. However, there remains a problem that space is limited in an evaluation system, for example the evaluation device portion of an evaluation system, which in use may be located in a production hall of a chip manufacturing plant, which means that the number of charged particle devices that can be positioned to scan samples of typical size is limited. Therefore, the present invention is directed to increasing the throughput of samples. Summary of the invention

[0007] An object of the present disclosure is to provide embodiments of a charged particle device.

[0008] According to a first aspect of the present invention, a charged particle device is provided for projecting charged particle beams of multiple beam grids to multiple samples. The device includes an array of a stage and charged particle devices. The stage is configured to support multiple samples at corresponding sample positions. The charged particle devices are respectively configured to project multiple charged particle beams in the beam grid to corresponding sample positions. The charged particle devices respectively include an array of objective lenses and a detector, the objective lenses are configured to guide corresponding light beams of the beam grids of the charged particle devices to the samples at corresponding sample positions, and the detectors are configured to detect signal particles from the samples. The stage is configured to be actuated relative to the array of charged particle devices. The stage and the array of charged particle devices are configured so that the array of charged particle devices is scanned simultaneously relative to the multiple samples. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The above and other aspects of the present disclosure will become more apparent through the description of exemplary embodiments with reference to the attached drawings.

[0010] Figure 1 is a schematic diagram illustrating an exemplary electron beam evaluation apparatus.

[0011] Figure 2 is shown as Figure 1 Schematic diagram of an exemplary multi-beam charged particle evaluation system of a portion of an exemplary electron beam evaluation apparatus.

[0012] Figure 3 is a schematic diagram of an exemplary multi-beam charged particle device.

[0013] Figure 4 is a schematic diagram of an exemplary charged particle device including an array of collimator elements and an array of scanning deflectors.

[0014] Figure 5 is a schematic diagram of an exemplary multi-beam charged particle device.

[0015] Figure 6 Yes Figure 4 Schematic diagram of a charged particle device of a plurality of charged particle devices.

[0016] Figure 7A-7C is a schematic diagram of an exemplary embodiment of a charged particle apparatus including arrays of charged particle devices in different arrangements and corresponding samples.

[0017] Figure 8A-B are schematic diagrams providing different views of an exemplary stage including a coarse actuator, a substage, and a sample holder.

[0018] Fig. 9 is a schematic diagram of an exemplary stage including a central sample holder surrounded by other sample holders.

[0019] The schematic diagrams and views show the components described below. However, the components depicted in the figures are not drawn to scale. DETAILED DESCRIPTION

[0020] Reference will now be made in detail to exemplary embodiments, examples of which are shown in the accompanying drawings. The following description refers to the accompanying drawings, wherein the same numbers in different figures represent the same or similar elements unless otherwise specified. The implementations set forth in the following description of exemplary embodiments do not represent all implementations consistent with the present invention. Instead, they are merely examples of devices and methods consistent with aspects related to the present invention as described in the appended claims.

[0021] The increase in computing power of electronic devices has led to a reduction in the physical size of the devices, which can be achieved by significantly increasing the packing density of circuit elements such as transistors, capacitors, diodes, etc. on IC chips. This is achieved by increasing the resolution, which allows smaller structures to be manufactured. For example, a thumbnail-sized IC chip for a smartphone, which will be launched in 2019 or earlier, may contain more than 2 billion transistors, each less than one thousandth the size of a human hair. Semiconductor IC manufacturing is therefore a complex and time-consuming process involving many individual steps. An error in one of the steps can seriously affect the functionality of the final product. The goal of the manufacturing process is to improve the yield of the entire process. For example, to achieve a 75% yield for a 50-step process (where the step indicates the number of layers formed on the wafer), the yield of each individual step must be greater than 99.4%. If the yield of each step is 95%, the yield of the entire process will be as low as 7%.

[0022] While high process yield is desirable in IC chip fabrication plants, it is also essential to maintain high substrate (i.e., wafer) throughput (defined as the number of substrates processed per hour). High process yield and high substrate throughput may be compromised by the presence of defects. This is especially true if operator intervention is required to inspect the defect. Therefore, high throughput detection and identification of micro- and nano-scale defects by evaluation systems (e.g., or including scanning electron microscopes ("SEM")) is critical to maintaining high yields and low costs.

[0023] The SEM includes a scanning device and a detection device. The scanning device includes an irradiation device and a projection device, wherein the irradiation device includes an electron source for generating primary electrons and the projection device is used to scan a sample (e.g., a substrate) with one or more focused primary electron beams. The irradiation device (or irradiation system) and the projection device (or projection system) can at least be collectively referred to as an electron optical system or device. The primary electrons interact with the sample and generate secondary electrons. The detection device captures secondary electrons from the sample while scanning the sample so that the SEM can create an image of the scanned area of ​​the sample. Such an evaluation device can utilize a single primary electron beam incident on the sample. For high-throughput inspection, some evaluation devices use multiple focused primary electron beams, i.e., multi-beams. The component beams of the multi-beams can be referred to as sub-beams or beam waves. The sub-beams can be arranged relative to each other in the multi-beam arrangement within the multi-beam. The multi-beam can scan different parts of the sample simultaneously. Therefore, the multi-beam evaluation device can evaluate (e.g., inspect) the sample at a faster speed than the single-beam evaluation device.

[0024] The implementation of known multi-beam evaluation devices and systems is described below.

[0025] The drawings are schematic. Therefore, for the sake of clarity, the relative sizes of the components in the figures are exaggerated. In the following description of the figures, the same or similar reference numbers refer to the same or similar components or entities, and only the differences with respect to the various embodiments are described. Although the description and drawings are directed to electron optical systems, it should be understood that the embodiments are not intended to limit the present disclosure to specific charged particles. Therefore, references to electrons in this document can be considered more generally as references to charged particles, where the charged particles are not necessarily electrons.

[0026] Reference now Figure 1 , which is a schematic diagram illustrating an exemplary charged particle beam evaluation apparatus 100. It should be noted that the evaluation apparatus comprises a portion of an evaluation system, typically a portion of an evaluation system located in a manufacturing facility. The evaluation apparatus may cover a surface area of ​​the manufacturing facility floor, referred to as an apparatus footprint. Other portions of the evaluation system (e.g., service systems and remote processing racks for vacuum and fluid supply) may be located elsewhere in the manufacturing facility, away from other manufacturing systems and apparatus with lower space requirements.

[0027] Figure 1 The charged particle beam evaluation apparatus 100 includes a main chamber 10, a load lock chamber 20, a charged particle evaluation system 40 (also referred to as an electron beam system or tool), an equipment front end module (EFEM) 30, and a controller 50. The charged particle evaluation system 40 is located in the main chamber 10.

[0028] The EFEM 30 includes a first loading port 30a and a second loading port 30b. The EFEM 30 may include additional loading ports. The first loading port 30a and the second loading port 30b may, for example, receive a substrate front opening pod (FOUP) containing a substrate (e.g., a semiconductor substrate or a substrate made of other materials) or a sample to be evaluated (e.g., measured or inspected) (substrates, wafers, and samples are collectively referred to as "samples" hereinafter). One or more robotic arms (not shown) in the EFEM 30 transport the sample to the load lock chamber 20.

[0029] The load lock chamber 20 is used to remove gas around the sample. This creates a vacuum, i.e., a local gas pressure that is lower than the pressure of the surrounding environment. The load lock chamber 20 can 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 lower than atmospheric pressure. After reaching the first pressure, one or more robotic arms (not shown) transport the sample from the load lock chamber 20 to the main chamber 10. The main chamber 10 is connected to a main chamber vacuum pump system (not shown). The main chamber vacuum pump system removes gas particles in the 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 a charged particle evaluation system 40, by which it can be evaluated. The charged particle evaluation system 40 includes a charged particle device 41. The charged particle device 41 can be an electron optical device, which can be synonymous with an electron optical system. The charged particle device 41 can be a multi-beam charged particle device 41, which is configured to project multiple beams to the sample, for example, the sub-beams are arranged relative to each other in a multi-beam arrangement. Alternatively, the charged particle device 41 may be a single beam charged particle device 41 configured to project a single beam towards the sample.

[0030] The controller 50 is electrically connected to the charged particle evaluation system 40. The controller 50 may be a processor (eg, a computer) configured to control the charged particle beam evaluation apparatus 100. The controller 50 may also include processing circuits configured to perform various signal and image processing functions. Figure 1The controller 50 is shown as being located outside the structure including the main chamber 10, the load lock chamber 20 and the EFEM 30, but it is understood that the controller 50 can be part of the structure. The controller 50 can be located in one component element of the charged particle beam evaluation device, or can be distributed on at least two component elements. Although the present disclosure provides an example of a main chamber 10 that houses an electron beam evaluation device, it should be noted that the aspects of the present disclosure in its broadest sense are not limited to a chamber that houses an electron beam evaluation device. On the contrary, it is understood that the aforementioned principles can also be applied to other tools and other device arrangements that operate at a second pressure.

[0031] Reference now Figure 2 , which is a schematic diagram showing an exemplary charged particle evaluation system 40, which includes a multi-beam charged particle device 41, the multi-beam charged particle device 41 is Figure 1 A portion of an exemplary charged particle beam evaluation device 100 of the present invention. The multi-beam charged particle device 41 includes an electron source 201 and a projection device 230. The charged particle evaluation system 40 also includes an actuation stage 209 and a sample holder 207. The sample holder may have a holding surface (not depicted) for supporting and holding a sample. Thus, the sample holder may be configured to support a sample. Such a holding surface may be an electrostatic clamp that is operable to hold a sample during operation of the charged particle device 41, such as to evaluate (e.g., measure or inspect) at least a portion of the sample. The holding surface may be recessed in the sample holder, such as a surface of the sample holder facing the charged particle device 41. The electron source 201 and the projection device 230 may be collectively referred to as a charged particle device 41. The sample holder 207 is supported by the actuation stage 209 so as to hold a sample 208 (e.g., a substrate or mask) for evaluation. The multi-beam charged particle device 41 also includes a detector 240 (e.g., an electronic detection device).

[0032] The electron source 201 may include a cathode (not shown) and an extractor or anode (not shown). During operation, the electron source 201 is configured to emit electrons from the cathode as primary electrons. The extractor and / or anode extract or accelerate the primary electrons to form a primary electron beam 202.

[0033] The projection device 230 is configured to convert the main electron beam 202 into a plurality of beamlets 211, 212, 213 and direct each beamlet onto the sample 208. Although only three beamlets are shown for simplicity, there may be tens, hundreds or thousands of beamlets. The beamlets may be referred to as beamlets.

[0034] The controller 50 may be connected to Figure 1The controller 50 may be used to control various parts of the charged particle beam evaluation device 100, such as the electron source 201, the detector 240, the projection device 230 and the actuator stage 209. The controller 50 may perform various image and signal processing functions. The controller 50 may also generate various control signals to control the operation of the charged particle beam evaluation device (including the charged particle multi-beam device).

[0035] The projection device 230 can be configured to focus the beamlets 211, 212, and 213 onto the sample 208 for evaluation, and can form three detection points 221, 222, and 223 on the surface of the sample 208. The projection device 230 can be configured to deflect the primary beamlets 211, 212, and 213 to scan the detection points 221, 222, and 223 across the respective scanning areas in a portion of the surface of the sample 208. In response to the primary beamlets 211, 212, and 213 being incident on the detection points 221, 222, and 223 on the sample 208, electrons are generated from the sample 208, which include secondary electrons and backscattered electrons. The secondary electrons typically have an electron energy of ≤50eV. The energy of the actual secondary electrons can be less than 5eV, but any electrons below 50eV are generally regarded as secondary electrons. The electron energy of the backscattered electrons is typically between 0eV and the landing energy of the primary beamlets 211, 212, and 213. Since the detected electrons with energy less than 50 eV are generally regarded as secondary electrons, a portion of the actual backscattered electrons will be regarded as secondary electrons.

[0036] The detector 240 is configured to detect signal particles (eg, secondary electrons and / or backscattered electrons) and generate corresponding signals, which are sent to the signal processing system 280, for example, to construct an image of the corresponding scanned area of ​​the sample 208. The detector 240 may be incorporated into the projection device 230.

[0037] The signal processing system 280 may include circuitry (not shown) configured to process signals from the detector 240 to form an image. The signal processing system 280 may also be referred to as an image processing system. The signal processing system may be incorporated into a component of the multi-beam charged particle evaluation system 40, such as the detector 240 (e.g., Figure 2As shown). However, the signal processing system 280 can be incorporated into any component of the evaluation device 100 or the multi-beam charged particle evaluation system 40, for example as part of the projection device 230 or the controller 50. The signal processing system 280 may include an image acquirer (not shown) and a storage device (not shown). For example, the signal processing system may include a processor, a computer, a server, a mainframe, a terminal, a personal computer, any type of mobile computing device, etc., or a combination thereof. The image acquirer may include at least part of the processing function of the controller. Therefore, the image acquirer may include at least one or more processors. The image acquirer may be communicatively coupled to the detector 240 to allow signal communication, such as an electrical conductor, a fiber optic cable, a portable storage medium, IR, Bluetooth, the Internet, a wireless network, radio, etc., or a combination thereof. The image acquirer may receive a signal from the detector 240, may process the data contained in the signal, and may construct an image therefrom. Therefore, the image acquirer may acquire an image of the sample 208. The image acquirer may also perform various post-processing functions, such as generating a contour, superimposing an indicator on the acquired image, etc. The image acquirer may be configured to perform adjustments such as brightness and contrast on the acquired image. The memory may be a storage medium such as a hard disk, a flash drive, cloud storage, random access memory (RAM), other types of computer-readable memory, etc. The memory may be coupled to the image acquirer and may be used to save the scanned raw image data as raw images and post-processed images.

[0038] The signal processing system 280 may include measurement circuitry (e.g., an analog-to-digital converter) to obtain a distribution of the detected secondary electrons. The electron distribution data collected during the detection time window may be used in conjunction with the corresponding scan path data of each primary beamlet 211, 212, and 213 incident on the sample surface to reconstruct an image of the sample structure being evaluated. The reconstructed image may be used to reveal various features of the internal or external structure of the sample 208. Thus, the reconstructed image may be used to reveal any defects that may be present in the sample.

[0039] The controller 50 may control the actuator stage 209 to move the sample 208 during evaluation (e.g., inspection) of the sample 208. The controller 50 may cause the actuator stage 209 to move the sample 208 in a certain direction (preferably continuously, e.g., at a constant speed) at least during the sample evaluation. The controller 50 may control the movement of the actuator stage 209 so that it changes the movement speed of the sample 208 according to various parameters. For example, the controller 50 may control the speed of the stage (including its direction) according to the characteristics of the evaluation step of the scanning process.

[0040] Known multi-beam systems, such as the above-mentioned charged particle evaluation system 40 and the charged particle beam evaluation device 100, are disclosed in US2020118784, US20200203116, US2019 / 0259570 and US2019 / 0259564, which are incorporated herein by reference.

[0041] like Figure 2 As shown, in one embodiment, the charged particle evaluation system 40 has a single charged particle device 41 and optionally includes a projection assembly 60. The projection assembly 60 can be a module and can be referred to as an ACC module. The projection assembly 60 is arranged to direct a light beam 62 so that the light beam 62 enters between the charged particle device 41 and the sample 208.

[0042] When the electron beam scans the sample 208, due to the large beam current, charges may accumulate on the sample 208, affecting the imaging quality. In order to adjust the charges accumulated on the sample, the projection assembly 60 may be used to irradiate the light beam 62 onto the sample 208 to control the charges accumulated due to effects such as photoconductivity, photoelectric or thermal effects.

[0043] Combine the following Figure 4 Components of a charged particle evaluation system 40 that may be used with the present invention are described. Figure 3 is a schematic diagram of a charged particle evaluation system 40, Figure 3 The charged particle evaluation system 40 may correspond to the charged particle evaluation system 40 mentioned above (which may also be referred to as an apparatus or a tool).

[0044] The electron source 201 directs electrons to a condenser lens array 231 (also referred to as a condenser lens array). The electron source 201 is preferably a high brightness thermal field emitter, which is arranged to operate within an optimized electron optical performance range, which is a compromise between brightness and total emission current (this compromise can be considered a "good" compromise). The electron source emits a source beam. There may be tens, hundreds, or thousands, or even tens of thousands of condenser lenses 231. The condenser lens 231 may include a multi-electrode lens and have a construction based on EP1602121A1, which document specifically incorporates the disclosure of the lens array by reference here to divide the source beam into a plurality of sub-beams. The top beam plate (which may be referred to as a beam limiting aperture array, and may be the top beam plate of the condenser lens array) may generate a plurality of beams. The array condenser lens (which may include a beam limiting aperture array) may provide a lens for each sub-beam. The condenser lens array 231 may take the form of at least two plates, used as electrodes, with the apertures in each plate aligned with each other and corresponding to the position of the sub-beam. During operation, at least two plates are held at different potentials to achieve the desired lens effect.

[0045] In one arrangement, the condenser lens array 231 consists of an array of three plates, where charged particles have the same energy when entering and leaving each lens, and this arrangement can be called a single lens. Therefore, dispersion only occurs within the single lens itself (between the entrance and exit electrodes of the lens), thereby limiting off-axis chromatic aberration. When the thickness of the condenser lens is low (e.g., a few millimeters), the effect of this aberration is small or negligible.

[0046] Each condenser lens 231 in the array directs electrons into corresponding sub-beams 211, 212, 213, which are focused at the respective intermediate focus down-beams of the condenser lens array. The sub-beams diverge from each other. In one embodiment, a deflector 235 is provided at the intermediate focus. The deflector 235 is located at or at least around the position of the corresponding intermediate focus in the path of the sub-beams. The deflector 235 is located in or near the path of the sub-beams at the intermediate image plane of the relevant sub-beams. The deflector 235 is configured to operate on the corresponding sub-beams 211, 212, 213. The deflector 235 is configured to bend the corresponding sub-beams 211, 212, 213 to a certain amount to ensure that the main ray (which may also be referred to as the beam axis) is incident on the sample 208 substantially vertically (i.e., substantially 90° to the nominal surface of the sample). The deflector 235 may also be referred to as a collimator or a collimator deflector. The deflector 235 actually collimates the paths of the beamlets so that before the deflector, the beamlet paths are divergent relative to each other. In the downlink beam of the deflector, the beamlet paths are substantially parallel relative to each other, i.e., substantially collimated. A suitable collimator is the deflector disclosed in EP application 20156253.5 filed on February 7, 2020, which is incorporated herein by reference to illustrate the application of deflectors in multi-beam arrays. In one embodiment of the device, the collimator may include a macro-collimator, instead of or in addition to the deflector 235. The macro-collimator may be electrostatic, for example as two planar plates with a single aperture.

[0047] There is a control lens array 250 at the bottom (i.e., the downlink beam or away from the source 201). The sub-beams 211, 212, and 213 passing through the deflector 235 are substantially parallel when entering the control lens array 250. The control lens pre-focuses the sub-beams (for example, applies a focusing action to the sub-beams before the sub-beams reach the objective lens array 241). Prefocusing can reduce the divergence of the sub-beams or increase the convergence rate of the sub-beams. The control lens array 250 and the objective lens array 241 operate together to provide a combined focal length. The combined operation without an intermediate focus can reduce the risk of aberrations. In one embodiment, the control lens of the control lens array can be regarded as a part of the objective lens of the objective lens array. The electrode plate of the control lens array can be regarded as an additional electrode plate of the objective lens array in electronic optics.

[0048] The landing energy is preferably determined using the control lens array 250. However, it is also possible to control the landing energy using the objective lens array 241 in addition. In this case, the potential difference across the objective lens changes when different landing energies are selected. An example of a situation in which it is best to partially change the landing energy by changing the potential difference across the objective lens is to prevent the focus of a beamlet from being too close to the objective lens. In this case, there is a risk that the components of the objective lens array 241 must be too thin to be manufactured. The same is true for the detector in this position. This situation may occur, for example, in the case of a reduced landing energy. This is because the focal length of the objective lens is roughly proportional to the landing energy used. By reducing the potential difference across the objective lens, and thus reducing the electric field within the objective lens, the focal length of the objective lens becomes larger again, resulting in a focus position further below the objective lens. Please note that using only the objective lens limits the control of the magnification. This arrangement does not allow control of the reduction ratio and / or the opening angle. In addition, using the objective lens to control the landing energy may mean that the objective lens will operate away from its optimal field strength. Unless the mechanical parameters of the objective lens (such as the spacing between its electrodes) can be adjusted, for example by replacing the objective lens.

[0049] The control lens array 250 includes a plurality of control lenses. Each control lens includes at least two electrodes (e.g., two or three electrodes) connected to respective potential sources. The control lens array 250 may include two or more (e.g., three) plate electrode arrays connected to respective potential sources. The control lens array 250 is associated with the objective lens array 241 (e.g., the two arrays are close to each other and / or mechanically connected and / or controlled together as a unit). Each control lens may be associated with a respective objective lens. The control lens array 250 is located at the uplink beam of the objective lens array 241.

[0050] The control lens array 250 includes a control lens for each sub-beam 211, 212, 213. The function of the control lens array 250 is to optimize the opening angle of the light beam to narrow the light beam and / or control the light beam energy transmitted to the objective lens array 241, which guides the sub-beams 211, 212, 213 onto the sample 208. The objective lens array 241 can be located at the bottom or near the charged particle device 41. The control lens array 250 is optional, but is preferably used to optimize the sub-beam uplink beam of the objective lens array. In the arrangement, the control lens array 250 can be regarded as a part of the objective lens array. The board of the control lens array can be regarded as an additional board of the objective lens array. In the objective lens array that meets this definition, in addition to the functions of the objective lens array described here, the function of the control lens array can also be the function of the objective lens array.

[0051] For the sake of convenience, the lens array is schematically shown in this article as an elliptical array (eg Figure 3 as well as Figure 4 and Figure 5). Each ellipse represents a lens in the lens array. Ellipses are often used to represent lenses, similar to the biconvex shapes often used in optical lenses. However, in the context of charged particle arrangements (such as the arrangements discussed herein), it should be understood that lens arrays typically operate electrostatically and therefore any physical elements that use biconvex shapes may not be required. The lens array can instead include multiple plates with apertures.

[0052] A scanning deflector array 260 may be provided between the control lens array 250 and the objective lens array 234. The scanning deflector array 260 includes a scanning deflector for each beamlet 211, 212, 213. Each scanning deflector is configured to deflect the corresponding beamlet 211, 212, 213 into one or two directions, thereby scanning the beamlet onto the sample 208 from one or two directions.

[0053] This is like Figure 3 As shown, a schematic diagram of an exemplary charged particle device has an objective lens array assembly. The objective lens array assembly includes an objective lens array 241. The objective lens array 241 includes a plurality of objective lenses. Each objective lens includes at least two electrodes (e.g., two or three electrodes) connected to a corresponding potential source. The objective lens array 241 may include two or more (e.g., three) plate electrode arrays connected to a corresponding potential source. Each objective lens formed by the plate electrode array may be a microlens that operates on different sub-beams or sub-beam groups in a plurality of beams. Each plate defines a plurality of apertures (also referred to as holes). The position of each aperture in the plate corresponds to the position of a corresponding aperture (or corresponding hole) in another plate (or multiple plates). The corresponding apertures define the objective lens, so that each group of corresponding holes operates on the same sub-beam or sub-beam group in a plurality of beams in use. Each objective lens projects a corresponding sub-beam of a plurality of beams onto the sample 208.

[0054] The objective lens array assembly also includes a control lens array 250. The control lens array 250 includes a plurality of control lenses. Each control lens includes at least two electrodes (e.g., two or three electrodes) connected to a corresponding potential source. The control lens array 250 may include two or more (e.g., three) plate electrode arrays connected to a corresponding potential source. The control lens array 250 is associated with the objective lens array 241 (e.g., the two arrays are close to each other and / or mechanically connected and / or controlled together as a unit). The control lens array 250 is located upstream of the beam of the objective lens array 241. The control lens pre-focuses the sub-beam. (e.g., a focusing action is applied to the sub-beam before the sub-beam reaches the objective lens array 241). Pre-focusing can reduce the divergence of the sub-beam or increase the convergence rate of the sub-beam. The control lens array and the objective lens array operate together to provide a combined focal length. The combined operation without an intermediate focus can reduce the risk of aberrations. In one embodiment, the control lens array can be considered as part of the objective lens array.

[0055] Figure 3 In the arrangement of, the objective lens array assembly includes a scanning deflector array 260. The scanning deflector array 260 includes a plurality of scanning deflectors. The scanning deflector array 260 can be formed using MEMS manufacturing technology. Each scanning deflector scans a corresponding sub-beam above or across the sample 208. Therefore, the scanning deflector array 260 can include a scanning deflector for each sub-beam. Each scanning deflector can deflect the light in the sub-beam to one direction (e.g., parallel to a single axis, such as the X-axis) or two directions (e.g., relative to two non-parallel axes, such as the X-axis and the Y-axis). The deflection causes the sub-beam to scan across the sample 208 in one or two directions (i.e., one dimension or two dimensions). In one embodiment, the scanning deflector described in EP2425444 can be used to implement the scanning deflector array 260, which is hereby incorporated by reference in its entirety, particularly the part about the scanning deflector. The scanning deflector array 260 is located between the objective lens array 241 and the control lens array 250. In the illustrated embodiment, a scanning deflector array 260 is provided in place of a macro-scanning deflector, such as an electrostatic scanning deflector (not shown). The scanning deflector array 260 may be more spatially compact than a macro-scanning deflector.

[0056] The objective lens array assembly may include a detector 240. (Alternatively, the detector may be included in the charged particle device 41 and need not be present in the objective lens array assembly). The detector 240 may include a detector element 405 (e.g., a sensor element, such as a capture electrode). The detector 240 may include any suitable type of detector. For example, the detector element may be a charged detector configured to detect charge detected relative to time, such as a current, a scintillator, or using a semiconductor device, such as a PIN element. The detector 240 may be a DC detector or an indirect current detector.

[0057] The detector 240 may be located between the objective lens array 241 and the sample 208. The detector 240 is configured as the lowest down-beam feature of the electron optics, e.g., close to the sample 208. The detector 240 may be very close to the sample 208, e.g., less than 5 mm, 3 mm, 1.5 mm, 300 μm, preferably between 200 and 10 μm, more preferably between 100 and 30 μm, e.g., less than or equal to about 50 μm.

[0058] The detector 240 may be positioned in the device so as to face the sample 208. Alternatively or additionally, the detector 240 may be positioned elsewhere in the electron optical system 41 so that the portion of the electron optical device that faces the sample 208 is not a detector and is therefore not a detector; for example, an electrode of an objective device. In such a device, another element of the electron optical device may face the sample during operation, such as an electrode plate of the objective. In all of these devices, the lowest beam element of the electron optical system (e.g., the detector 240) is closest to the sample. The lowest beam surface of the lowest beam element may face the sample. The lowest beam surface may be referred to as a facing surface.

[0059] The bottom surface of the detector 240 (or the facing surface of the detector 240, which may face the sample 208 when in use) may include a substrate 404 on which a plurality of detector elements 405 are disposed. Each detector element 405 may surround a beam aperture 406. The beam aperture 406 may be formed by etching the substrate 404. In this arrangement, the beam apertures 406 are in a hexagonal close-packed array, or in a rectangular array. The detector elements 405 may be arranged in a rectangular array or a hexagonal array.

[0060] In the cross section of the detector, the detector element 405 forms the bottommost portion of the detector 240, i.e., the surface closest to the sample 208. A logic layer 407 may be provided between the detector element 405 and the bulk of the substrate 404. At least a portion of the signal processing system may be incorporated into the logic layer 407. A wiring layer 408 is provided on the back side or inside the substrate 404 and is connected to the logic layer 407 via substrate through-holes 409. The wiring layer 408 may include control lines, data lines, and power lines. A printed circuit board and / or other semiconductor chip may be provided on the back side of the detector 240, for example, connected to the back side of the detector 240.

[0061] The detector 240 can be implemented by integrating a CMOS chip detector into an electrode of the objective lens array 241 (e.g., a bottom electrode of the objective lens array 241). Integrating the detector 240 into the objective lens array 241 or other components of the electron optical system 41 allows detection of electrons emitted relative to a plurality of corresponding sub-beams. The CMOS chip can embody the detector, which can be oriented to face the sample. In one embodiment, a detector element 405 for capturing secondary charged particles is formed in a surface metal layer of the CMOS device. The detector element 405 can be formed in other layers. The power supply and control signals of the CMOS can be connected to the CMOS vias. The passive silicon substrate with holes isolates the CMOS chip from high E fields, for example, to provide robustness.

[0062] In order to maximize detection efficiency, it is best to make the surface of the detector elements 405 as large as possible so that substantially all of the area of ​​the objective lens array 240 (except the apertures) is occupied by the detector elements 405. Additionally or alternatively, the diameter of each detector element 405 is substantially equal to the array pitch (i.e., the aperture pitch of the aperture array in the electrodes of the objective lens assembly 241). The diameter of each detector element can be less than about 600 μm, and preferably between about 50 μm and 500 μm. The pitch can be selected based on the expected distance between the sample 208 and the detector 240. In one embodiment, the shape of the detector elements 405 is circular, but they can be made square to maximize the detection area. The diameter of the through hole 409 that passes through the substrate can be minimized. Typical sizes of electron beams are about 5 to 15 μm.

[0063] In one embodiment, a single detector element 405 surrounds each beam aperture 406. In another embodiment, a plurality of detector elements 405 are disposed around each beam aperture 406.

[0064] In other embodiments, for example, Figure 4 A variation of the arrangement shown and described in , in which both a macro scanning deflector 265 and a scanning deflector array 260 are provided. In such an arrangement, scanning of the beamlets on the sample surface can be achieved by simultaneously controlling the macro scanning deflector and the scanning deflector array 260 (preferably synchronously).

[0065] Providing a scanning deflector array 260 rather than a macro-scanning deflector can reduce aberrations of the control lens. This is because the scanning action of the macro-scanning deflector causes the light beam to move accordingly on a beam shaping limiter (also called a downstream beam limiter) that defines a beam downstream beam limiting aperture array of at least one electrode of the control lens, which increases the aberrations of the control lens. When a scanning deflector array 260 is used, the amount of light beam movement on the beam shaping limiter is much smaller. This is because the distance from the scanning deflector array 260 to the beam shaping limiter is much shorter. Therefore, it is best to place the scanning deflector array 260 as close to the objective lens array 241 as possible (for example, so that the scanning deflector array 260 is directly adjacent to the objective lens array 241, such as Figure 4As shown). The smaller the movement on the beam shaping limiter, the smaller the portion used by each control lens. Therefore, the control lens has a smaller aberration contribution. In order to minimize or at least reduce the aberration caused by the control lens, the beam shaping limiter is used to shape the beam from at least one electrode of the control lens. This is structurally different from conventional systems, in which the beam shaping limiter is only provided as an aperture array that is part of or associated with a first manipulator array in the beam path and typically generates multiple beams from a single beam from the source. In one arrangement, the beam shaping limiter 262 is structurally integrated with the electrodes of the objective lens array 241. Ideally, the beam shaping limiter 262 is located in an area of ​​low electrostatic field strength. Each beam limiting aperture of the beam shaping limiter 262 is aligned with a corresponding objective lens in the objective lens array 241. This alignment allows a portion of the sub-beam from the corresponding objective lens to pass through the beam limiting aperture and impinge on the sample 208. Each beam limiting aperture has a beam limiting effect, allowing only a selected portion of the beamlets incident on the beam shaping limiter 262 to pass through the beam limiting aperture. The selected portion may be such that only a portion of the corresponding beamlet that passes through the central portion of each aperture in the objective lens array reaches the sample. The central portion may have a circular cross-section and / or be centered on the beam axis of the beamlet.

[0066] like Figure 4 As shown, control lens array 250 is the first deflection or lens electron optical array element in the beam path downstream of source 201.

[0067] Figure 4 In an embodiment, a collimator element array 271 is provided to replace the macro collimator, which can be an electrostatic collimator having two or more plates with a single aperture (which can be in the form of a macro collimator lens, such as an electrostatic lens). The collimator element array 271 can be more compact in space than the macro collimator 270. Therefore, providing the collimator element array 271 and the scanning deflector array 260 together can save space. This space saving is ideal when multiple electron optical systems including objective lens array assemblies are provided in the electron optical system array. In such an embodiment, there may be no macro condenser lens or condenser lens array. Therefore, in this case, the control lens provides the possibility of optimizing the beam opening angle and magnification to change the landing energy.

[0068] like Figure 4 As shown, collimator element array 271 is the first deflection or focusing electron optical array element in the beam path downlink of source 201.

[0069] Avoiding any deflection or lensing of the electron optical array elements (e.g., lens arrays or deflector arrays) that control the uplink beam of the lens array 250 or the uplink beam of the collimator element array 271 reduces the requirements for the electron optical uplink beam of the objective lens and the corrector for correcting defects in such optical devices. For example, some alternative arrangements attempt to maximize source current utilization by providing a condenser lens array in addition to the objective lens array. Providing a condenser lens array and an objective lens array in this manner results in strict requirements for the position of the virtual source position uniformity over the source opening angle, or requires corrective optics for each beamlet to ensure that each beamlet passes through the center of its corresponding objective lens downlink beam. The architecture shown in FIG. 4 allows the beam path from the first deflection or lens electron optical array element to the beam shaping limiter to be reduced to less than about 10 mm, preferably less than about 5 mm, preferably less than about 2 mm. Reducing the beam path can reduce or eliminate strict requirements for the virtual source position over the source opening angle.

[0070] In one embodiment, an array of electron optical systems is provided. The array may include any electron optical system described herein. Each electron optical system focuses its own multiple beams simultaneously onto different regions of the same sample. Each electron optical system may form sub-beams from charged particle beams from different respective sources 201. Each respective source 201 may be one of the multiple sources 201. At least a subset of the multiple sources 201 may be provided as a source array. The source array may include multiple sources 201 disposed on a common substrate. Focusing multiple multiple beams simultaneously onto different regions of the same sample allows a larger area of ​​the sample 208 to be processed (e.g., evaluated) simultaneously. The electron optical systems in the array may be arranged adjacent to each other so as to project the corresponding multiple beams onto adjacent regions of the sample 208. Any number of electron optical systems may be used in the array. Preferably, the number of electron optical systems is in the range of 9 to 200. In one embodiment, the electron optical systems are arranged in a rectangular array or a hexagonal array. In other embodiments, the electron optical systems are provided in an irregular array or a regular array having a geometric shape other than a rectangle or a hexagon. Each electron optical system in the array may be configured in any manner described herein when referring to a single electron optical system. As described above, scanning deflector array 260 and collimator element array 271 are particularly suitable for incorporation into an array of electron optical systems because their spatial compactness facilitates positioning the electron optical systems close to each other.

[0071] like Figure 4As shown, the objective lens array assembly (including the unit of the objective lens array 241) further includes a beam shaping limiter 242. The beam shaping limiter 262 defines a beam limiting aperture array. The beam shaping limiter 242 may be referred to as a downstream beam shaping limiting aperture array or a final beam limiting aperture array. The beam shaping limiter 242 may include a plate (which may be a plate-shaped body) having a plurality of apertures. The beam shaping limiter 242 controls the beam downward from at least one electrode (optionally from all electrodes) of the lens array 250. In some embodiments, the beam shaping limiter 242 is directed downward from at least one electrode (optionally from all electrodes) of the objective lens array 241.

[0072] In some embodiments, the charged particle device 41, such as Figure 4 Shown and referenced Figure 4 The beam shaping limiter 242 further includes an upper beam limiter 252, for example, in addition to the beam shaping limiter 242. The upper beam limiter 252 defines a beam limiting aperture array. The upper beam limiter 252 may be referred to as an upper beam limiting aperture array or an uplink beam limiting aperture array. The upper beam limiter 252 may include a plate (which may be a plate-like body) having a plurality of apertures. The upper beam limiter 252 forms a beamlet from the charged particle beam emitted from the source 201. Portions of the beam other than those that contribute to forming the beamlet may be blocked (e.g., absorbed) by the upper beam limiter 252 so as not to interfere with the beamlets of the downlink beam. The charged particles projected through the apertures in the upper beam limiter 252 may come from the beamlets. The upper beam limiter 252 may be referred to as a beamlet defining aperture array.

[0073] Any objective lens array assembly described herein may also include a detector 240 having any of the features described. The detector detects electrons emitted from the sample 208. The detected electrons may include any electrons detected by the SEM, including secondary electrons and / or backscattered electrons emitted from the sample 208.

[0074] Figure 5 A charged particle evaluation system 40 according to an embodiment is schematically shown. Features identical to those described above are given the same reference numerals. For the sake of brevity, these features are no longer referred to. Figure 5 For example, the source 201, the condenser lens 231, the macro collimator 270, the objective lens array 241 and the sample 208 may be as described above.

[0075] As described above, in one embodiment, the detector 240 is located between the objective lens array 241 and the sample 208. The detector 240 may face the sample 208. Alternatively, Figure 5As shown, in one embodiment, an objective lens array 241 including a plurality of objective lenses is located between the detector 240 and the sample 208. In addition to the features described herein, the detector 240 can have all the features of the previously described embodiments (e.g., reference Figure 3 and Figure 4 ).

[0076] In one embodiment, the deflector array 95 is located between the detector 240 and the objective lens array 241. In one embodiment, the deflector array 95 includes a Wien filter (or even an array of Wien filters), and thus the deflector array can be referred to as a beam splitter. The deflector array 95 is configured to provide a magnetic field to separate charged particles projected onto the sample 208 from secondary electrons from the sample 208. However, the system preferably includes electrostatic elements rather than magnetic elements.

[0077] In one embodiment, the detector 240 is configured to detect signal particles by reference to the energy of the charged particles (i.e., depending on the band gap). Such a detector can be a semiconductor-based detector, such as a PIN detector or a scintillator (which is optically connected to a photon converter or a photon to electron converter). Such a detector 240 can be referred to as an indirect current detector. The secondary electrons emitted from the sample 208 gain energy from the field between the electrodes. The secondary electrode has sufficient energy once it reaches the detector 240.

[0078] The control lens array 250 may be located in the same module as the objective lens array 241, ie forming an objective lens array assembly, or, in one term, being part of the objective lens array, or it may be located in a separate module.

[0079] In some embodiments, for example, reference Figure 3 , Figure 4 and Figure 5 In any of the embodiments described and shown in the figures, one or more aberration correctors are provided to reduce one or more aberrations in the beamlets. One or more aberration correctors may be provided in any embodiment, for example as part of a charged particle optical device, and / or as part of an optical lens array assembly, and / or as part of an evaluation system, and / or as part of an electron optical device. In one embodiment, each of the aberration correctors of at least a subset is located in or directly adjacent to a corresponding one of the intermediate focuses (e.g., in or adjacent to an intermediate image plane). The beamlets have a minimum cross-sectional area in or near the focal plane (e.g., the intermediate plane). This provides more room for aberration correctors than elsewhere (i.e., an uplink beam or a downlink beam at the intermediate plane) (or more space than is available in an alternative arrangement without an intermediate image plane).

[0080] In one embodiment, an aberration corrector located in or directly adjacent to the intermediate focus (or intermediate image plane) includes a deflector to correct for the situation where the light source 201 appears to be in different positions for different beams. The corrector can be used to correct for macroscopic aberrations caused by the light source that would prevent good alignment between each beamlet and the corresponding objective.

[0081] The aberration corrector can correct aberrations that prevent proper column alignment. Such aberrations can also cause misalignment between the beamlets and the corrector. Therefore, it may be desirable to additionally or alternatively position the aberration corrector at or near the condenser lens 231 (e.g., each such aberration corrector is integrated with or directly adjacent to one or more condenser lenses 231). This is ideal because at or near the condenser lens 231, the aberrations also do not cause a shift in the corresponding beamlets because the condenser lens is vertically close to or coincides with the beam aperture. However, the challenge of positioning the corrector at or near the condenser lens is that the beamlets have a relatively large cross-sectional area and a relatively small spacing at this position relative to a position further downstream. The aberration corrector can be a CMOS-based individually programmable deflector, as disclosed in EP2702595A1, or can be a multi-pole deflector array, as disclosed in EP2715768A2, the descriptions of the beamlet manipulators in both documents being incorporated herein by reference.

[0082] In some embodiments, each of at least a subset of aberration correctors is integrated with or directly adjacent to the objective lens array 241. In one embodiment, these aberration correctors reduce one or more of: field curvature; focus error; and astigmatism. Additionally or alternatively, one or more scanning deflectors (not shown) can be integrated with or directly adjacent to the objective lens array 241 for scanning the beamlets 211, 212, 213 over the sample 208. In one embodiment, the scanning deflectors described in US2010 / 0276606, which is hereby incorporated by reference in its entirety, can be used.

[0083] like Figure 2 As shown (when combined with Figures 3 to 5 In one embodiment, the projection assembly 60 optionally includes an optical system 63. In one embodiment, the projection system 60 includes a light source 61. The light source 61 is configured to emit a light beam 62. As described above, the projection assembly 60 is used to irradiate the light beam 62 onto the sample 208 to control the charge accumulated due to effects such as photoconductivity, photoelectric or thermal effects; thereby adjusting the charge accumulated on the sample.

[0084] In one embodiment, the optical system 63 includes a cylindrical lens 64. The cylindrical lens 64 is configured to focus the light beam 62 more in one direction rather than in an orthogonal direction. The cylindrical lens increases the design freedom of the light source 61. In one embodiment, the light source 61 is configured to emit a light beam 62 having a circular cross-section.

[0085] It is not essential to provide a cylindrical lens 64. In an alternative embodiment, another optical component can be used that is able to focus more strongly in one direction than in another direction. In an alternative embodiment, the light source is configured to emit, for example, an elliptical or rectangular beam 62. This is desirable despite the small size between the sample and the lowest descending beam surface of the charged particle device 41, and the large size of the descending beam surface of the electron optical device orthogonal to the beam path direction, to ensure that the beam reaches the portion of the sample that needs to be irradiated.

[0086] In one embodiment, the optical system 63 includes reflective surfaces 65, 66, such as mirrors. For example, two reflective surfaces 65, 66 may be provided. In an alternative embodiment, the optical system 63 does not reflect the light beam 62. The number and arrangement of the reflective surfaces may be selected based on the size of the volume in which the projection system 60 needs to be installed. Such reflective surfaces may help improve the reach of the light beam 62 between the lowest beam surface of the charged particle device and the sample.

[0087] The invention disclosed herein can be applied to a variety of different tool architectures. The charged particle device includes multiple columns and multiple beams. Each column may include a charged particle device, such as the charged particle device 41 described in any of the above embodiments or aspects. As multiple columns (or multiple columns of devices) including multiple devices (or multiple device arrays), the devices can be arranged in an array, and the number of arrays can be two to one hundred or more (or can be included in two to one hundred columns). The charged particle device can be used as Figure 6 The embodiment shown is a device comprising a plurality of charged particle devices 41, as described above with reference to Figure 4 The charged particle device preferably has an electrostatic scanning deflector array and an electrostatic collimator array. The charged particle array may optionally include a source. It should be noted that in different arrangements, the devices in the multi-device array may adopt any suitable design, such as Figure 3 or Figure 5 The design shown and described in (not shown).

[0088] The front surface of the charged particle device of the multi-device array includes an active area and a mechanical area. The active area includes the surface of the charged particle optical components, such as a detector (e.g., the detector array preferably includes an aperture array for a beam grid) or a lens electrode (e.g., a plate with an aperture array for a beam grid path). (In this context, the multiple beams can be referred to as a beam grid. The beams can have a positional relationship to each other, such as in a grid. Therefore, the beam grid can be a plurality of beams having a cross-sectional pattern that determines their positional relationship. The beam grid path can be a multi-beam path). 7A to 7C In FIG. 4 , the active region may be represented by circle 404. The mechanical region may be the surface of a component used to support and isolate one or more charged particle optical components (e.g., a plate electrode or a detector array). The component used to support and isolate the charged particle component may be a gasket. 7A to 7C , the mechanical region can be represented by a hexagon 402 around a circular representation of the surface of the charged particle optical element. The outline of the hexagon represents the radial extension of the facing surface of the charged particle device relative to the beam grid path direction, for example separating two charged particle devices, and the exterior of the charged particle device group or multi-device array (for the charged particle device positioned most outwardly relative to the corresponding group and / or multi-device array). The outline does not have to be a hexagon, but any suitable shape, such as a rectilinear, rectangular, square or diamond, as defined by the geometric arrangement of the charged particle device with the corresponding group of charged particle devices and the optional multi-device array.

[0089] Figure 7A-7C Plan views of three different arrangements of charged particle devices are provided for projecting a beam grid of multiple charged particle beams onto multiple samples.Such a grid may include multiple charged particle beams, which may be obtained from a common source beam (ie, a single source), for example. Fig. 7A The device includes a stage 209 and a plurality of charged particle devices 41 arranged in an array. The stage 209 is configured to support a plurality of samples 208 at various sample positions (e.g., two sample positions, i.e., two samples 208). Such samples can be supported at their sample positions by a sample holder 207. Note that reference to sample positions herein is intended to refer to the support of the sample by the sample holder. The stage may include a plurality of sample holders, for example, as many sample holders as there are samples. The charged particle devices 41 are respectively configured to project a plurality of charged particle beams in a beam grid to the sample positions. In other words, each charged particle device 41 is configured to project multiple beams of charged particles to a sample 208 at one of the corresponding sample positions on the stage 209. In one embodiment, it is noteworthy that a more efficient arrangement of charged particle devices can be achieved without a projection assembly 60 for each device. This arrangement can allow for a more compact arrangement of devices, such as a design when a projection assembly may conflict with the volume required for an adjacent charged particle device.

[0090] In one arrangement, the stage 209 is configured to be actuated relative to the array of charged particle devices 41. The stage 209 and the array of charged particle devices 41 are configured such that the array of charged particle devices is scanned relative to multiple samples 208 simultaneously. The stage 209 and the array of charged particle devices 41 may be configured such that at least one of the multiple sample positions (e.g., including the sample holder 207) is configured to be actuated relative to at least one charged particle device 41. Alternatively or additionally, the array of charged particle devices 41 may be configured to be actuated relative to the stage 209 such that the array of charged particle devices 41 is scanned relative to multiple samples.

[0091] In another arrangement, the stage 209 is configured to actuate a sample position (e.g., sample holder 207) relative to the array of charged particle optical devices 41. Specifically, the stage 209 and the array of charged particle devices 41 can be configured so that at least one of the plurality of sample positions is configured to be actuated relative to at least one of the array of charged particle devices 41. In this way, at least one of the charged particle optical devices 41 and the plurality of sample positions can be scanned relative to each other. Specifically, the stage 209 and the array of charged particle devices 41 can be configured so that the stage and the array of charged particle optical devices can be actuated relative to each other. The stage 209 and the array of charged particle optical devices 41 are optionally configured so that the device array 41 scans relative to a plurality of sample positions simultaneously.

[0092] In any of these arrangements of devices, there are multiple sample positions on the same stage, and samples located at each sample position can be scanned simultaneously. Therefore, the throughput of samples processed (e.g., evaluated) by the device is increased compared to a device configured to scan only one sample at a time. For example, each charged particle device can be used for sample evaluation. Because a device or machine is configured to support and evaluate multiple samples simultaneously, the device can evaluate more samples per hour. This will save cost and space, such as equipment footprint in a chip manufacturing facility, compared to the need for multiple completely independent machines, each of which only evaluates (e.g., measures or inspects) one sample at a time. Specifically, using this arrangement, some components can be shared between multiple samples in the same machine / device.

[0093] The charged particle device may include, for example, a vacuum chamber. The stage may be disposed within the vacuum chamber. With the present arrangement, there are multiple sample positions on the stage, so that multiple samples can be evaluated simultaneously using only one vacuum chamber. In contrast, if it is desired to evaluate multiple samples simultaneously using a device / machine having a stage configured to support only a single sample, multiple devices / machines will be required, which means that multiple separate vacuum chambers will need to be provided and maintained. Therefore, the present arrangement can reduce installation, operation and maintenance costs without adversely affecting sample throughput.

[0094] The charged particle device 41 may correspond to Figure 4 and Figure 6 However, alternative charged particle devices, such as those described above with respect to Figure 3 and Figure 5 Described. Specifically, each charged particle device includes an objective lens and a detector. The objective lens is configured to direct the beam grid of the charged particle device onto the sample at the corresponding sample position. The detector is configured to detect signal particles from the sample. In an embodiment, the detector may provide a facing surface of a different charged particle optical device to face the sample during operation, or a surface of an objective lens electrode. (Note that references to the objective lens and detector may be viewed as references to an objective lens array and a detector array, respectively. Each objective lens in the objective lens array may have a corresponding detector of the detector array. Each objective lens in the objective lens array may operate on a corresponding light beam of the beam grid.)

[0095] The objective lens (or array of objective lenses) is preferably electrostatic. It is preferred that the charged particle optical components of each charged particle device are electrostatic rather than magnetic. If magnetic components are used, the charged particle devices may need to be sufficiently spaced apart from each other, and the spacing distance should reduce the risk of magnetic interference between the charged particle devices. Therefore, it may be preferable to use electrostatic components because it allows the charged particle devices in the array to be grouped more tightly. This can increase the number of charged particle devices that can simultaneously project a charged particle beam onto a single sample. In turn, a greater number of charged particle devices dedicated to each sample may further help increase the throughput of samples processed on the device.

[0096] The array of charged particle devices may include multiple groups of charged particle devices, each group including multiple charged particle devices. The charged particle device groups are configured to project multiple charged particle beams in the beam grid to corresponding sample positions. In other words, each group of charged particle devices can be arranged so that the charged particle devices in the group are configured to project the charged particle beam to a specific sample position in the multiple sample positions.

[0097] Fig. 7A and Figure 7B In the arrangement, adjacent groups of charged particle devices are spaced apart from each other. Fig. 7A The arrangement shown in Figure 7B The arrangement shown in differs in that Fig. 7A The arrangement shown in has a two-dimensional array of sample positions and a two-dimensional array of charged particle device groups, rather than arranging multiple sample positions and charged particle device groups in a linear array (such as Figure 7B For example (as shown in the figure), Fig. 7A The arrangement in has two sample locations and two corresponding groups of charged particle devices; while Figure 7B The arrangement shown in has four sample locations and two corresponding groups of charged particle devices. Fig. 7A and Figure 7B In an arrangement such as the one in FIG. 1 , there may be a benefit that the space between the charged particle device groups can be used to store the support electronics and the architecture of the charged particle device groups. Such use of space can provide easier maintenance access. Fig. 7A and Figure 7B In the arrangement in , each group of charged particle devices can be assigned to a different sample position. Therefore, the number of groups of charged particle devices is preferably equal to the number of sample positions.

[0098] Figure 7C In the arrangement of , adjacent groups of charged particle devices are not spaced apart from each other. Figure 7C In the arrangement, the groups of charged particle devices are adjacent to each other so that there is an array of individual charged particle devices that is continuous between different groups. That is, the charged particle devices are arranged in a continuous two-dimensional array or a continuous array (e.g., a continuous multi-device array). The continuous array can have a facing surface configured to face the table so that some devices face the sample position of the table and other devices face positions between the table away from the sample position or toward the periphery of the table. Figure 7C In an arrangement of , there may be an advantage that not all charged particle devices may be allocated or dedicated to only one specific sample position. Instead, there may be charged particle devices configured to project charged particle beams to a plurality of different sample positions at respective times.

[0099] Fig. 7A - In any of the arrangements of FIG. C, the groups of charged particle devices are configured to face their respective sample positions, or at least a range of positions that the sample positions and the groups of charged particle devices may assume during a scan. Each group of charged particle devices may be configured to project a plurality of beam grids to a respective sample position, or at least a portion of a range of positions that the sample positions may assume during a scan. For example, at certain sample positions, the charged particle devices may appear to be located at a reference position. Figure 7Cbetween the sample positions in the illustrated and described embodiments. The sample positions may each have a corresponding origin position. The origin position may be the center position of the sample position position range. The sample position may be configured to deviate from the origin position during scanning, with a maximum distance equal to a spacing between one charged particle device in each group of charged particle devices facing the sample position. Multiple charged particle devices may be configured to face the position range of the sample position during scanning. For example, the central charged particle device may be the central charged particle device facing the sample position at the origin position of the sample position. Another charged particle device facing the sample position may be a charged particle device that is offset from the central charged particle device by a distance at least equal to the spacing between adjacent charged particle devices in the charged particle device group. Different beam grids in a charged particle device group may correspond to different charged particle devices in a charged particle device group.

[0100] Fig. 7A and Figure 7B In an arrangement, the number of charged particle devices in each group of charged particle devices is 7. In other arrangements, the number of charged particle devices in each group of charged particle devices can be between 2 and 100, preferably between 7 and 37 in one embodiment, and more preferably between 7 and 19. It is desirable to have more charged particle devices in each group so that more devices can be dedicated to scanning the same sample simultaneously. This has the benefit of faster sample scanning, thereby increasing sample throughput. However, the space available on each sample is limited, and the sample can be a disk with a diameter of 300 mm. Therefore, due to the size of each charged particle device and its supporting electronics and structure, the number of charged particles that can simultaneously project a charged particle beam onto the same sample may be limited by space constraints.

[0101] like Figure 7A-7C As shown, in one arrangement, the charged particle devices of each group have a hexagonal arrangement. However, the charged particle devices can be arranged in a straight line, a rectangle, a square, a rhombus or any other suitable geometric arrangement. For example, the array of charged particle devices may include two or more rows of charged particle devices, wherein these rows are arranged in a plane across the beam grid path of at least one charged particle device. These rows may include at least three charged particle devices. Preferably, two or more rows of charged particle devices are parallel to each other. Alternatively, two or more rows of charged particle devices may be array charged particle device rows with different directions. The hexagonal arrangement may be preferred because it enables the charged particle devices to be optimally tightly packed within the arrangement. Therefore, the charged particle devices are arranged into a continuous two-dimensional array. In the array of charged particle devices, the device is surrounded by at least four devices (e.g., six devices), which are located in different directions. For example, the two-dimensional array is at least a three-by-three array in at least two directions of the array, and the arrays are angled relative to each other.

[0102] like Figure 7A-7C In the arrangement shown, in each group of charged particle devices 41, one charged particle optical device (which may be referred to as a reference device 42, such as a central charged particle device 42) is surrounded by other charged particle devices 43 in the group of charged particle optical devices 41 in a plane of a beam grid path across at least one charged particle optical device 41.

[0103] Fig. 7A and Figure 7B In the arrangement, each group includes a central charged particle device 42 located at the center of the group and a plurality of other charged particle devices 43. The other charged particle devices 43 are arranged around the central charged particle device 42 to form a charged particle device ring. (When more charged particle devices can be arranged around the other charged particle devices 43, the ring of other charged particle devices 43 can be referred to as an inner ring of charged particle devices). However, there can be less than six charged optical devices in the charged optical device ring. It is preferred that there are at least four charged particle devices in the ring, and each charged particle device in the ring is located at a different position in the plane of the charged particle device, for example, across the path of the charged particle beam in the beam grid, for example, orthogonal to the path of the beam grid (for example, the XY plane) relative to the central charged particle device. The charged particle devices in the ring can be positioned in different directions relative to the beam grid path (or charged particle axis) of the central charged particle device in the plane across the beam grid path. The four charged particle devices in the ring can be located in different directions, i.e., four different directions from the charged particle axis of the central charged particle device. Preferably, the four different directions include at least one pair of directions opposite to each other. In an arrangement, the four different directions include two pairs of directions opposite to each other. Each pair of directions opposite to each other has a common direction. There may be two common directions that are orthogonal to each other.

[0104] Optionally, another circle (or ring) of additional charged particle devices can be arranged around the inner ring to form, for example, an outer ring of charged particle devices relative to the inner ring. The inner ring charged particle device 43 is adjacent to the central charged particle device 42. The optional outer ring charged particle device can be adjacent to the inner ring charged particle device. In the case of being adjacent to the inner ring, another circle of charged particle devices can be compactly arranged, thereby preferably minimizing the volume use of a multi-device array with additional charged particle devices. Another circle of charged particle devices can surround the inner ring and other circles (i.e., a charged particle device circle between another circle of charged particle devices and the central charged particle device in the charged particle device group). The charged particle device circle with the device farthest from the central charged particle device or from the center of the sample position can be called, for example, the outermost ring charged particle device within a group of charged particle devices. The arrangement in which the central charged particle device is surrounded by one or more other charged particle device rings enables the charged particle device to be compactly arranged within a group of charged particle devices in a multi-device arrangement. Such a group of charged particle devices can be compactly arranged to optimize (e.g., maximize) the number of charged particle devices in a group of charged particle devices facing the corresponding sample position. That is, the arrangement of charged particle devices within the multi-device array is intended to effectively utilize the space facing the sample (i.e., the facing surface facing the sample position).

[0105] One or more groups of charged particle devices may be configured to be actuated in at least one degree of freedom relative to the stage and / or each other. Preferably, all groups of charged particle devices are configured to be actuated. Preferably, the charged particle devices are configured to be actuated in a direction along a beam grid of at least one charged particle optical device of the charged particle optical device array, preferably each group of charged particle optical devices. When the sample is placed in each sample position, the direction along the beam grid may be perpendicular to the major surface of the sample.

[0106] Fig. 8A A side view of an exemplary stage 209, two sample holders 207, and two sets 45 of charged particle devices 41 is provided. The stage 209 includes a coarse actuator 210 and two sub-stages 215. Figure 8B Provided Fig. 8A A plan view of the stage 209 and the sample holder 207. Fig. 8A As shown, each group 45 of charged particle devices 41 is configured to be actuated at least in the Z direction. The Z direction may be perpendicular to Fig. 8A and Figure 8B Although the figure shows an arrangement with two sample positions and two groups of charged particle devices, the description can be applied to an arrangement with any number of sample positions and the same number of groups of charged particle devices, or a continuous charged particle device arrangement.

[0107] To facilitate driving the stage and the groups 45 of charged particle devices 41 relative to each other. Each group 45 may include an actuator device configured to drive the group of charged particle optical devices within the charged particle optical device array. Alternatively or additionally, the charged particle devices of different groups of charged particle devices may include electron optical elements configured to operate the charged particle beams of the corresponding beam grids so as to drive the corresponding group of charged particle devices relative to other groups of charged particle devices and / or corresponding sample positions.

[0108] Preferably, each group of charged particle devices is configured to actuate in at least one degree of freedom. Each group of charged particle devices is optionally configured to actuate in up to six degrees of freedom. The ability to actuate each group of devices in the direction of the charged particle beam of the charged particle devices in at least the same group can contribute to sample processing. Specifically, actuating each group of devices can optimally position the group of devices relative to the sample located at each sample position. Preferably, each group of devices is configured to actuate individually so as to be positioned facing its respective sample (e.g., above the sample). Therefore, the charged particle beam is guided and focused on the sample.

[0109] Additionally or alternatively, one or more charged particle devices 41 in the array (preferably all charged particle devices) may be configured to be individually actuated in at least one degree of freedom. Preferably, the individual actuations are in a direction along the beam grid path of the charged particle optics, preferably perpendicular to a major surface of the sample at the respective sample position, preferably perpendicular to the plane of the major surface. Such a major surface of the sample may be the front surface of the sample facing the one or more charged particle devices. For example, in Fig. 8A In the arrangement shown, each charged particle device 41 is configured to be actuated in at least the Z direction. The Z direction may be perpendicular to Fig. 8A and Figure 8B The scanning and sub-scanning directions (X direction and Y direction) of the stage 209 are, for example, substantially parallel to one or more beam grids in a set of charged particle devices 41 .

[0110] For ease of actuation, the charged particle device comprises a plurality of actuators. One of the plurality of actuators may be associated with each charged particle device. Each actuator is preferably configured to drive the corresponding charged particle device relative to another charged particle device and / or the sample position, for example in one or more degrees of freedom, for example perpendicular to the plane of the sample position, around a direction perpendicular to the plane of the sample position, (e.g. rotation) and / or tilting, for example rotation along a direction in the plane of the sample position.

[0111] Alternatively or additionally, the charged particle device may respectively include one or more electron optical elements configured to operate the light beam of the beam grid of the charged particle optical device. The one or more electron optical elements may be configured to operate the beam grid to drive the light beam of the beam grid, such as one or more electrode plates of an objective lens array (e.g., a control lens array). The light beam of the beam grid may be driven relative to the charged particle optical device array and / or the corresponding sample position of the charged particle optical device group to which the corresponding charged particle optical device belongs and / or the beam grid of other charged particle optical devices.

[0112] Preferably, each charged particle device is configured to be actuated in at least one degree of freedom. Each charged particle device is optionally configured to be actuated in up to six degrees of freedom. The ability to actuate each charged particle device at least in the direction of the charged particle beam of the same group of charged particle devices can facilitate sample processing. Specifically, actuating the charged particle device can optimally position the charged particle device relative to the sample located at the corresponding sample position. Preferably, each charged particle device is configured to be actuated individually so as to be positioned near (e.g., above) its corresponding sample so that the charged particle beam is correctly guided and focused on the sample. However, the ability to actuate each charged particle device individually may increase the complexity of the device. Therefore, preferably, a group of charged particle devices can be actuated; but each charged particle device cannot be actuated individually. Therefore, a group of charged particle devices (e.g., a group of charged particle devices) can be actuated; therefore, the charged particle device can be driven in the form of a multi-charged particle device group. Alternatively or additionally, it may be advantageous to drive the sample relative to the charged particle device. Additionally or alternatively, the stage may have an actuator to actuate one or more sample positions relative to the group of charged particle devices.

[0113] Fig. 7A , Fig. 8A and Figure 8B The stages shown in each provide two sample positions, which are arranged in one plane, in particular in the XY plane. However, in alternative arrangements, there may be more than two sample positions on the stage. The stage may provide four sample positions, for example Figure 7B and Figure 7C There may be 2 to 20 sample locations, preferably 2 to 9, more preferably 5 to 9. Fig. 9 A plan view of the stage 209 and sample holder 207 is provided. Fig. 9 The arrangement shown in Figure 8B The arrangement is the same as in Figure 8B The arrangement in FIG. 1 comprises two sample positions, arranged on respective sample holders 207, and Fig. 9 The arrangement in includes 9 sample positions on 9 sample holders 207.

[0114] The stage may include at least 5 sample positions, preferably 9 sample positions, such as Fig. 9 As shown. The sample positions can be arranged in a plane and can include a central sample position with sample positions around the central sample position, preferably in four directions of the plane. Fig. 9 As shown, the four directions may include at least one pair of directions opposite to each other, for example Fig. 9 X and / or Y direction; or, four directions are two pairs of sample positions placed in opposite directions of the central sample position. With such an arrangement, a relatively large number of samples can be provided on the same table, which can increase sample throughput, processing speed (e.g., evaluation speed), and sample surface area. In addition, by providing up to nine sample positions on the same table, the device footprint can be much smaller than the total footprint of nine different devices.

[0115] The stage 209 and / or the sample holder 207 (also referred to as a sample holder) may be configured to support individual samples. The stage may actuate the sample positions so as to actuate the samples located at the sample positions. At least one of the sample positions may be configured to actuate in at least one degree of freedom, and preferably in three to six degrees of freedom, such as at least three of the following: in the plane of the sample position, such as the X and Y directions; in the direction of the path around the beam grid, such as the Rz direction; in a direction orthogonal to the plane of the same position, such as in the z direction, and at an angle or tilt relative to the sample position, such as Rx and Ry.

[0116] Fig. 8A , Figure 8B and Fig. 9 In the arrangement of , the stage 209 includes a coarse actuator 210. The coarse actuator is configured to actuate a plurality of samples. Fig. 8A As shown in Figure 8B, the coarse actuator 210 can be configured to actuate in at least one translational degree of freedom, and preferably in three translational degrees of freedom (X, Y and / or Z directions). Preferably, the actuation is in a direction (X and / or Y direction) in the plane of the path of the device beam grid across the device array, ideally perpendicular to the path. The coarse actuator can optionally actuate all sample positions by tilting the stage relative to the direction of the beam grid of the charged particle device array, such as rotating about the X direction (Rx) and / or rotating about the Y direction (Ry). In this way, the coarse actuator can actuate the sample in the scan direction and / or sub-scan direction.

[0117] The coarse actuator is preferably configured to actuate at least one sample position to change the relative position of the beam of the beam grid between different positions on the sample surface at the sample position. The different positions correspond to different instances of the repeating pattern of the sample.

[0118] In the arrangement shown, the coarse actuator is configured to collectively actuate all of the plurality of samples. In an alternative arrangement, the coarse actuator may be configured to actuate a plurality of sample positions of the plurality of sample positions, but not all of the sample positions.

[0119] Fig. 8A , Figure 8B and Fig. 9 The charged particle device of WO 2011 / 026858 comprises a plurality of sample holders 207, also referred to as sample holders. Each sample holder is configured to support a sample at one of the corresponding sample positions.

[0120] In the layout, Fig. 9 As shown, the sample holders 207 are arranged on the stage 209 into a two-dimensional array of sample holder arrays. Fig. 9 In the sample support array shown, one sample support 207 of the sample support array is surrounded by other sample supports 207 of the sample support array.

[0121] The sample holder array can be formed in Fig. 9 In an alternative arrangement. The sample holder array preferably includes sample holders 207 for two or more rows of sample positions. The sample holder 207 row may include two or more rows of adjacent sample holders, for example arranged in a linear array. The sample position rows preferably each include at least three adjacent sample positions. One or more of the multiple rows of sample positions may extend along the stage direction. Two or more rows of sample holders in the sample holder array are rows of different sample holders. The sample holder array has two or more rows of sample holders; two or more rows of sample holders in the sample holder array have different directions.

[0122] The sample holder 207 of the sample holder array is preferably arranged to have a planar support surface that straddles the beam grid path of at least one charged particle optical device of the charged particle optical device array. The sample holder array is preferably located in a plane that straddles the beam grid path of at least one charged particle optical device of the charged particle optical device array (e.g., Fig. 9 XY plane), preferably perpendicular to the beam grid path.

[0123] The sample holders are each configured to be actuated with at least one degree of freedom, preferably three to six degrees of freedom. The sample holder 207 is configured to be actuated relative to the charged particle device 41, such as Fig. 8A , Figure 8B and Fig. 9 shown.

[0124] The sample holder may be configured to be actuated in at least one rotational degree of freedom. Preferably, the sample holder is configured to rotate about a direction passing through the plane of the main surface of the sample at the sample location (preferably perpendicular to this plane). This rotational movement may be about Fig. 8A and Figure 8BIn this way, samples can be individually rotated for alignment before being processed (e.g., evaluated) using a charged particle beam of a charged particle device. This rotation of the sample around the direction of the beam grid path can be used to resolve the relative rotational alignment between different beam grids of a charged particle device of a multi-device array. This can save time in aligning each of a plurality of samples to be processed simultaneously. With the time saved, the throughput of samples processed per unit time (e.g., hours or days) can be increased because the setup time for each sample is less compared to a device that does not perform alignment adjustments by actuating the sample holder.

[0125] For similar reasons, such as to save time and improve throughput, it is desirable to configure the sample holder 207 to be actuated separately, such as independently of actuation of another sample position, in a translation direction, such as along the path of the beam grid of the charged particle device in the corresponding charged particle device group. This translation direction along the beam grid path can correspond to the Z direction, such as Fig. 8A Independently actuating different sample positions along the beam grid path direction can adjust the relative focal position of the sample at the sample position with respect to the facing electron optics of the multi-device array.

[0126] Another translation direction may be a plane orthogonal to the beam grid path direction. Figure 8B In the embodiment of the present invention, this can be one or both of the X-axis and the Y-axis. Such actuation of each sample position can independently drive the samples (when present) so that they move parallel to the plane of the stage 209. Such movement can improve the alignment of the samples with one or more charged particle devices 41 in the multi-device array (for example, a corresponding group 45 of charged particle devices 41). Such charged particle devices may be misaligned, and such actuation can improve the average alignment of the charged particle devices: the group of charged particle devices; and / or the facing sample position.

[0127] Alternatively or additionally, the sample holder 207 may be configured to be independently actuated in one or two other rotational directions, which may be referred to as tilting relative to a plane orthogonal to the beam grid path direction. Fig. 8A As shown, preferably, the sample position is configured to be actuated in a rotational direction around the Y direction (Ry). Similarly, additionally or alternatively, the sample position is configured to be actuated in a rotational direction around the X direction (Rx). In this way, each sample can be tilted relative to the stage 209. This can improve the alignment of the sample with the charged particle device 41 in the corresponding group 45 of charged particle devices 41.

[0128] If the device is configured to drive each sample with enough degrees of freedom, the complexity of configuring multiple groups of charged particle devices or even driving each individual charged particle device can be avoided. This can reduce the complexity of the system and thus reduce the cost of construction, installation and maintenance.

[0129] like Fig. 8A and Figure 8B As shown, the number of groups 45 of charged particle devices 41 is equal to the number of sample holders 207. With this arrangement, each group of charged particle optical devices 45 can be assigned to a different sample holder 207. The charged particle devices 41 of each group are preferably configured to face the main surface of the sample supported by the sample holder at the corresponding sample position. In this way, the charged particle beam can be easily projected onto each of the multiple samples at the same time.

[0130] Fig. 8A , Figure 8B and Fig. 9 The device shown also includes a plurality of sub-stages, each of which is arranged at a corresponding sample position. Each sub-stage is configured to at least contribute to actuating one of the corresponding sample positions in at least one degree of freedom; for example, to actuate sample position 210 in at least one degree of freedom relative to the coarse actuator actuating the sample position. Each sub-stage may be configured to contribute to actuating one of the corresponding sample positions in at least three degrees of freedom (preferably six degrees of freedom). The sub-stage may be configured to actuate the sample position in the same direction as the coarse actuator. The sub-stage may be configured to actuate the sample position in a scanning direction and / or a sub-scanning direction. The actuation range of the sub-stage may be smaller than the actuation range of the coarse actuator. Actuation of the sub-stage may be achieved by one or more fine actuators, for example, there is at least one fine actuator for each degree of freedom of the fine actuator actuating the sample position. Such a fine actuator may be able to achieve a finer actuation displacement of the sample position than a coarse actuator.

[0131] Fig. 8A , Figure 8B and Fig. 9 In the arrangement of the embodiment of the present invention, the sub-stage 215 is disposed on the coarse actuator 210. In this arrangement, the sub-stage 215 is supported by the coarse actuator; each sub-stage 215 is configured to actuate a corresponding sample position relative to the coarse actuator 210. In these arrangements, the stage 209 includes the coarse actuator 210 and the sub-stage 215. The stage optionally also includes a sample holder 207.

[0132] Preferably, each sample position has a corresponding dedicated sub-stage. Fig. 8A , Figure 8B and Fig. 9 As shown, each sample holder 207 can be arranged on a different sub-stage 215. The sub-stage 215 is configured to actuate the sample holder 207. The multiple sub-stages can be configured to actuate at least two of the multiple sample positions independently of each other, and preferably all of the sample positions. With this arrangement, the position and scanning of each sample can be better controlled.

[0133] In an alternative arrangement, one or more sub-stages may be configured to actuate multiple sample positions together in at least one degree of freedom. For example, two adjacent sample positions may share the same sub-stage. Alternatively, in an arrangement without a sub-stage, the sample positions may be disposed on a sample holder 207 disposed directly on the coarse actuator 210.

[0134] Each sub-stage can be configured to actuate a corresponding sample position relative to the path of the beam grid of at least one of the array of charged particle devices. Preferably, the sub-stage can activate the sample position relative to the path of the beam grid of at least one of the charged particle device groups assigned to the corresponding sample position. Specifically, the sub-stage is ideally configured to actuate the sample position to change the relative position of the sub-beam within a repeating pattern structure of the sample and / or within a repeating pattern structure of a mark on the sub-stage (e.g., on a sample holder, such as on a sensor mounted on the sub-stage or the sample holder). Therefore, the sub-stage can provide a finer sample alignment than that provided by a coarse actuator. Therefore, for an actuation direction in which the sample position is effectively actuated by the coarse actuator and the fine actuator of the sub-stage, the fine actuator can be controlled to, for example, finely adjust the actuation of the coarse actuator in a specific degree of freedom.

[0135] XXX ArticleXXX

[0136] Reference to a component or component or element system that can be controlled to manipulate a charged particle beam in a certain manner includes configuring a controller or control system or control unit to control the component to manipulate the charged particle beam in the manner described, and optionally using other controllers or devices (such as voltage sources and / or current sources) to control the component to manipulate the charged particle beam in this manner. For example, a voltage source can be electrically connected to one or more components to apply a potential to the component under the control of a controller or control system or control unit, such as the control lens array 250, the objective lens array 241, the focusing lens 231, the corrector, the collimator element array, and the scanning deflector array 260 in a non-limiting list. An actuable component (such as a stage) can be controllable to actuate and thereby move relative to another component (such as a beam path), using one or more controllers, control systems, or control units to control the actuation of the component.

[0137] The embodiments described herein may take the form of a series of aperture arrays or electron optical elements arranged in an array along a beam or multi-beam path. (The multi-beam path may be referred to as a beam grid path or a path of a beam grid). Such electron optical elements may be electrostatic. In one embodiment, all electron optical elements (e.g., the last electron optical element in the sub-beam path from the beam limiting aperture array to the sample before) may be electrostatic and / or may be in the form of an aperture array or a plate array. In some arrangements, one or more electron optical elements are manufactured as a micro-electromechanical system (MEMS) (i.e., using MEMS manufacturing technology). For example, an aperture array, a plate electrode such as an objective lens array, one or more features of a detector array, a scanning deflector array, and an array of collimator elements may be formed using MEMS manufacturing technology.

[0138] References to above and below, up and down, above and below should be understood to refer to directions parallel (typically but not always perpendicular) to the directions of the up-beam and down-beam of the electron beam or beams impinging on the sample 208. Thus, references to up-beam and down-beam are intended to refer to the directions of the beam paths independent of any existing gravitational field.

[0139] An evaluation system according to an embodiment of the present disclosure may be a tool for performing a qualitative evaluation of a sample (e.g., pass / fail), a tool for performing a quantitative measurement of a sample (e.g., the size of a feature), or a tool for generating an image or map of a sample. Examples of evaluation systems are inspection tools (e.g., for identifying defects), inspection tools (e.g., for classifying defects), and metrology tools, or tools capable of performing any combination of evaluation functions associated with inspection tools, inspection tools, or metrology tools (e.g., metrology inspection tools). The electron optical column 40 may be a component of an evaluation system; for example, an inspection tool or a metrology inspection tool, or part of an electron beam lithography tool. Any reference to a tool herein is intended to cover an apparatus, device, or system comprising various components that may or may not be co-located, and may even be located in separate rooms, particularly, for example, for data processing elements.

[0140] References to above and below, up and down, above and below should be understood to refer to directions parallel (typically but not always perpendicular) to the directions of the up-beam and down-beam of the electron beam or beams impinging on the sample 208. Thus, references to up-beam and down-beam are intended to refer to the directions of the beam paths independent of any existing gravitational field.

[0141] The terms "beamlet" and "beamlet" are used interchangeably herein and are both understood to include any radiation beam derived from a parent radiation beam by dividing or splitting the parent radiation beam. The term "manipulator" is used to include any element that affects the path of a beamlet or beamlet, such as a lens or deflector.

[0142] Reference to an element being aligned along a beam path or a beamlet path is to be understood as referring to the respective element being positioned along the beam path or the beamlet path.

[0143] Although the present invention has been described in conjunction with various embodiments, other embodiments of the present invention will be apparent to those skilled in the art from the specification and practice of the invention disclosed herein. The specification and examples should be considered as exemplary only, and the true scope and spirit of the present invention are indicated by the following claims and clauses.

[0144] The following provisions are provided:

[0145] Item 1. A charged particle device for projecting charged particle beams of multiple beam grids onto multiple samples, the device comprising: a stage configured to support multiple samples at corresponding sample positions; and an array of charged particle devices (for example, a two-dimensional array of devices), the charged particle devices being respectively configured to project multiple charged particle beams in the beam grid onto the corresponding sample positions, the charged particle devices respectively comprising an objective lens (or an array of objective lenses) and a detector, the objective lens being configured to guide the beam grid of the charged particle device (or the corresponding light beam of the beam grid) onto the sample at the corresponding sample position, and the detector being configured to detect signal particles from the sample, the stage being configured to be actuated relative to the array of charged particle devices, and the stage and the array of charged particle devices being configured so that the array of charged particle devices is scanned simultaneously relative to the multiple samples.

[0146] Item 2. A charged particle apparatus according to Item 1, wherein the stage and the array of charged particle devices are configured such that at least one of the plurality of sample positions is configured to be actuated relative to at least one of the charged particle devices.

[0147] Item 3. A charged particle apparatus according to Item 1 or 2, wherein the array of charged particle devices is configured to be actuated relative to the stage so that the array of charged particle devices is scanned simultaneously relative to the plurality of samples.

[0148] Item 4. A charged particle device according to any of the preceding items, wherein the array of charged particle devices includes a charged particle device having two or more rows of at least three adjacent devices in a plane of a path of the beam grid across the charged particle device, the two or more rows being different rows of devices in the array, and the two or more rows having different directions in the array.

[0149] Item 5. A charged particle device according to Item 4, wherein the array of charged particle devices includes a charged particle device located within a plane of a path of the beam grid across the charged particle device surrounded by adjacent devices, preferably located in four different directions of the plane, preferably, the four directions include at least one pair of directions opposite to each other.

[0150] Clause 6. A charged particle device according to any preceding clause, wherein the detector comprises a detector array.

[0151] Item 7. A charged particle device according to any of the preceding items, wherein the detector is arranged at the downlink beam of the objective lens (or objective lens array), preferably, the detector has a downlink beam surface, which is the facing surface of the charged particle device, preferably, the facing surface faces one of the sample positions.

[0152] Clause 8. A charged particle apparatus according to any preceding clause, wherein the array of charged particle devices comprises a plurality of groups of charged particle devices, wherein the plurality of groups of charged particle devices are configured to project a plurality of charged particle beams in a beam grid to the respective sample positions.

[0153] Clause 9. The charged particle device of clause 8, wherein adjacent groups of charged particle devices are spaced apart from each other.

[0154] Clause 10. The charged particle device according to clause 8 or 9, wherein the charged particle devices of each group have a hexagonal arrangement or a linear arrangement, the linear arrangement is preferably a rectangular arrangement.

[0155] Clause 11. The charged particle device according to any one of clauses 8 to 10, wherein the number of charged particle devices in each group of charged particle devices is between 2 and 100, preferably between 7 and 37.

[0156] Clause 12. A charged particle device according to any one of clauses 8 to 11, wherein in each group at least one charged particle optical device is surrounded by other charged particle optical devices in the group within a plane across the beam grid path of the at least one charged particle optical device.

[0157] Item 13. A charged particle device according to Item 12, wherein each group includes a central charged particle device, which is preferably arranged at the center of the group, and preferably a plurality of charged particle devices are arranged around the central charged particle device to form at least one ring of charged particle devices, preferably, the at least one ring of charged particle devices includes an inner ring, which includes a charged particle optical device adjacent to the central charged particle device.

[0158] Clause 14. A charged particle device according to clause 13, wherein the at least one ring of charged particle optical devices comprises a plurality of rings of charged particle devices, preferably arranged around the inner ring, preferably the plurality of rings comprises an outer ring of charged particle devices adjacent to the inner ring of charged particle devices.

[0159] Clause 15. The charged particle apparatus according to any one of clauses 8 to 14, wherein the number of groups of charged particle devices is equal to the number of sample positions, preferably each group of charged particle devices is assigned to a different sample position.

[0160] Item 16. A charged particle device according to Item 15, wherein each group of charged particle devices is configured to project multiple beam grids to corresponding sample positions of the sample, preferably, different beam grids of the group of charged particle devices correspond to different charged particle devices in the group of charged particle devices.

[0161] Item 17. A charged particle device according to any one of Items 15 or 16, further comprising a plurality of sample holders, wherein each sample holder is configured to support a sample at one of the corresponding sample positions, wherein the number of groups is equal to the number of sample holders, preferably, each group of charged particle optical devices is assigned to a different sample holder.

[0162] Clause 18. A charged particle device according to any one of clauses 8 to 17, wherein the plurality of sets of charged particle optical devices are each configured to face a corresponding sample position, preferably a major surface of a sample supported by a sample holder, the sample holder preferably being located at the corresponding sample position.

[0163] Item 19. A charged particle device according to any one of items 8 to 18, wherein the multiple groups of charged particle optical devices are each configured to be actuated in at least one degree of freedom relative to the stage and / or relative to each other, preferably in the direction of a beam grid of at least one charged particle optical device of the array of charged particle optical devices, preferably in a corresponding group of charged particle optical devices, preferably along the direction of the beam grid perpendicular to the main surface of the sample, preferably perpendicular to the plane of the main surface of the sample at the corresponding sample position.

[0164] Clause 20. A charged particle apparatus according to clause 19, wherein the plurality of groups of charged particle devices each comprise an actuator arrangement configured to actuate the group of charged particle optical devices relative to the stage and within the array of charged particle optical devices.

[0165] Item 21. A charged particle device according to Item 19 or 20, wherein the charged particle devices in different groups of charged particle devices include electron optical elements, which are configured to operate the charged particle beam of the corresponding beam grid so as to actuate the charged particle devices of the corresponding group relative to other groups of charged particle devices and / or corresponding sample positions.

[0166] Item 22. A charged particle device according to any of the preceding items, wherein each charged particle device is configured to be individually actuated in at least one degree of freedom, preferably individually actuated in a direction along the beam grid path of the charged particle optical device, preferably perpendicular to the major surface of the sample at the corresponding sample position, preferably perpendicular to the plane of the major surface.

[0167] Clause 23. A charged particle apparatus according to clause 22, wherein associated with each charged particle device is an actuator configured to actuate the charged particle device relative to another charged particle device and / or a sample position.

[0168] Item 24. A charged particle device according to any of the preceding items, wherein the charged particle device respectively comprises one or more electron optical elements, and the one or more electron optical elements are configured to operate the light beam of the beam grid of the charged particle optical device, wherein the one or more electron optical elements are configured to operate the beam grid to actuate the light beam of the beam grid relative to a corresponding sample position and / or beam grids of other charged particle optical devices in an array of the charged particle optical devices and / or a group of charged particle optical devices to which the corresponding charged particle optical device belongs.

[0169] Item 25. A charged particle device according to any of the preceding items, wherein at least the corresponding sample position is configured to actuate the sample in a rotational degree of freedom, preferably rotating about a direction of a plane passing through a major surface of the sample at the sample position, preferably perpendicular to the plane, preferably relative to the path of a beam grid of at least one charged particle device in an array of charged particle devices, preferably relative to the path of a beam grid of at least one charged particle device in a group of charged particle devices assigned to the corresponding sample position.

[0170] Item 26. A charged particle device according to any of the preceding items (for example, item 25), wherein at least the corresponding sample position is configured to actuate the sample in at least one translational degree of freedom, preferably to actuate the sample in a direction of a plane passing through a major surface of the sample at the sample position, preferably perpendicular to the plane, and / or preferably to actuate the sample in a direction across a path of a beam grid of at least one of the charged particle devices toward the sample position, for example parallel to a plane of the major surface of the sample at the sample position, preferably relative to the path of a beam grid of at least one charged particle device in an array of charged particle devices, preferably relative to the path of a beam grid of at least one charged particle device in a group of charged particle devices assigned to the corresponding sample position.

[0171] Item 27. A charged particle device according to Item 25 or 26, wherein the stage comprises at least one sub-stage, which is configured to facilitate actuation of at least one of the corresponding sample positions in at least one degree of freedom, preferably in at least three degrees of freedom, and preferably in six degrees of freedom.

[0172] Item 28. A charged particle device according to Item 27, wherein the at least one sub-stage is configured to actuate a corresponding sample position in at least one degree of freedom relative to the path of the beam grid of at least one charged particle device in the array of charged particle devices, preferably relative to the path of the beam grid of at least one charged particle device in the group of charged particle devices assigned to the corresponding sample position.

[0173] Clause 29. A charged particle device according to clause 26 or 27, wherein the at least one sub-stage is configured to actuate the sample to change the relative position of the beamlets within the repeating patterned structure in the sample.

[0174] Item 30. A charged particle device according to any one of Items 25 to 29, wherein the stage comprises a plurality of sub-stages, wherein at least two of the plurality of sub-stages are configured to actuate at least two of the plurality of samples independently of each other, preferably wherein each sub-stage is arranged at a corresponding sample position.

[0175] Item 31. A charged particle device according to any of the preceding items, wherein the stage includes a coarse actuator, which is configured to actuate more than one of the multiple sample positions, preferably configured to actuate more than one of the multiple sample positions collectively, preferably to actuate all of the multiple samples collectively.

[0176] Item 32. A charged particle device according to Item 30, wherein the coarse actuator is configured to actuate the stage in at least one translational degree of freedom, preferably in a direction in the plane of a path of the beam grid across the devices in the array of devices, preferably perpendicular to the path.

[0177] Clause 33. A charged particle device according to clause 31 or 32, wherein the at least one sub-stage is supported by the coarse actuator and is configured to actuate a corresponding sample position relative to the coarse actuator.

[0178] Item 34. A charged particle device according to any one of items 31 to 33, wherein the coarse actuator is configured to actuate at least one of the sample positions to change the relative position of the light beam of the beam grid between different positions on the sample surface of the sample at the sample position, which different positions are different tube cores of the sample, preferably scanning the sample at different positions at different times.

[0179] Clause 35. A charged particle device according to any preceding clause, wherein the stage comprises a plurality of sample supports configured to support a substrate at a sample position.

[0180] Item 36. A charged particle device according to Item 35, wherein different sample holders are configured to be actuated relative to the stage, preferably at least two different sample holders of the stage are configured to be actuated relative to each other, and at least one, preferably at least two different sample holders are configured to be actuated relative to the stage.

[0181] Item 37. A charged particle device according to item 35 or 36, wherein the sample holder is arranged in a sample holder array in a two-dimensional array on the stage, across the path of the beam grid of at least one charged particle optical device in the array of charged particle optical devices, preferably, the sample holder array is located in a plane across the path of the beam grid of at least one charged particle optical device in the array of charged particle optical devices, and preferably, the plane is perpendicular to the path of the beam grid of at least one charged particle optical device in the array of charged particle optical devices.

[0182] Item 38. A charged particle device according to any one of Items 34 to 36, wherein the sample holder array comprises a sample holder having two or more rows of at least three adjacent samples, the two or more rows are different rows of sample holders in the sample holder array, and the two or more rows of sample holders have different directions in the sample holder array.

[0183] Item 39. A charged particle device according to Item 37 or 38, wherein at least one holder of the sample holder array is surrounded by other sample holders of the sample holder array, preferably in four different directions in the plane, preferably the four directions include at least one pair of mutually opposite directions.

[0184] Clause 40. A charged particle device according to any preceding clause, wherein the objective lens (or array of objective lenses) is electrostatic.

[0185] Clause 41. A charged particle apparatus according to any preceding clause, wherein each charged particle device is used for sample evaluation, preferably sample inspection.

[0186] Clause 42. The charged particle device of any preceding clause, further comprising a vacuum chamber, wherein the stage is arranged within the vacuum chamber.

[0187] The above description is intended to be illustrative only and not limiting. Therefore, it should be apparent to those skilled in the art that modifications may be made as described without departing from the scope of the following claims.

Claims

1. A charged particle device for projecting a plurality of beam grids of charged particle beams onto a plurality of samples, the device comprising: a stage configured to support a plurality of samples at respective sample positions; as well as Arrays of charged particle devices, The charged particle devices are respectively configured to project a plurality of charged particle beams in a beam grid to the corresponding sample positions, The charged particle devices respectively comprise an array of objective lenses configured to direct respective beams of the beam grid of the charged particle device onto the sample at the respective sample position, and a detector configured to detect signal particles from the sample, the stage being configured to be actuated relative to the array of charged particle devices, The stage and the array of charged particle devices are configured such that the array of charged particle devices is scanned simultaneously relative to the plurality of samples.

2. A charged particle device according to claim 1, wherein the stage and the array of charged particle devices are configured so that at least one sample position of the plurality of sample positions is configured to be actuated relative to at least one charged particle device of the charged particle devices.

3. A charged particle device according to claim 1 or 2, wherein the array of charged particle devices includes charged particle devices having two or more rows of at least three adjacent devices within a plane of a path of the beam grid across the charged particle devices, the two or more rows being rows of different devices in the array, and the two or more rows having different directions in the array.

4. A charged particle device according to claim 3, wherein the array of charged particle devices includes charged particle devices located in a plane across the path of the beam grid of the charged particle devices surrounded by adjacent devices, preferably the adjacent devices are located in four different directions of the plane, preferably, the four directions include at least one pair of directions opposite to each other.

5. A charged particle device according to any one of the preceding claims, wherein the detector comprises an array of detectors, preferably the detectors being arranged at a down-beam of the array of objectives.

6. A charged particle apparatus according to any one of the preceding claims, wherein the array of charged particle devices comprises a plurality of groups of charged particle devices, wherein the plurality of groups of charged particle devices are configured to project a plurality of charged particle beams in a beam grid to the respective sample positions.

7. The charged particle device of claim 6, wherein adjacent groups of charged particle devices are spaced apart from each other.

8. A charged particle device according to claim 6 or 7, wherein at least one charged particle optical device in each group is surrounded by other charged particle optical devices in the group in a plane across the beam grid path of at least one of the charged particle optical devices.

9. The charged particle apparatus according to any one of claims 6 to 8, wherein the number of groups of charged particle devices is equal to the number of sample positions, preferably each group of charged particle devices is assigned to a different sample position.

10. A charged particle device according to any one of claims 6 to 9, wherein the plurality of groups of charged particle optical devices are each configured to face a corresponding sample position, preferably a major surface of a sample supported by a sample holder, the sample holder preferably being located at the corresponding sample position.

11. A charged particle device according to any of the preceding claims, wherein each charged particle device is configured to be individually actuated in at least one degree of freedom, preferably individually actuated in a direction along the beam grid path of the charged particle optical device, the direction preferably being perpendicular to the major surface of the sample at the corresponding sample position, preferably perpendicular to the plane of the major surface.

12. A charged particle device according to any of the preceding claims, wherein the charged particle devices respectively comprise one or more electron optical elements, and the one or more electron optical elements are configured to operate the beam of the beam grid of the charged particle optical device, wherein the one or more electron optical elements are configured to operate the beam grid to actuate the beam of the beam grid relative to the corresponding sample position and / or the beam grids of other charged particle optical devices in the array of the charged particle optical devices and / or the group of charged particle optical devices to which the corresponding charged particle optical device belongs.

13. A charged particle device according to any of the preceding claims, wherein at least the corresponding sample position is configured to actuate the sample in a rotational degree of freedom, preferably rotating about a direction of a plane passing through a major surface of the sample at the sample position, the direction preferably being perpendicular to the plane, preferably relative to the path of a beam grid of at least one charged particle device in an array of charged particle devices, preferably relative to the path of a beam grid of at least one charged particle device in a group of charged particle devices assigned to the corresponding sample position.

14. A charged particle device according to any of the preceding claims, wherein at least the corresponding sample position is configured to actuate the sample in at least one translational degree of freedom, preferably to actuate the sample in a direction passing through a plane of a major surface of the sample at the sample position, the direction preferably being orthogonal to the plane of the major surface, and / or preferably to actuate the sample in a direction across a path of a beam grid of at least one of the charged particle devices toward the sample position, the direction being, for example, parallel to the plane of the major surface of the sample at the sample position, preferably relative to the path of the beam grid of at least one charged particle device in an array of charged particle devices, preferably relative to the path of the beam grid of at least one charged particle device in the group of charged particle devices assigned to the corresponding sample position.

15. A charged particle device according to any of the preceding claims, wherein the stage comprises a coarse actuator, which is configured to actuate more than one of the multiple sample positions, preferably configured to actuate more than one of the multiple sample positions collectively, preferably to actuate all of the multiple samples collectively.

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