Fluid transport system in charged particle systems

Abstract

Apparatus, systems, and methods for conveying fluid to a stage in a charged particle beam system are disclosed. In some embodiments, the stage may be configured to hold a wafer; a cavity may be configured to house the stage; and a tube may be disposed within the cavity to convey fluid between the stage and an exterior of the cavity. The tube may include a first tubular layer of a first material, wherein the first material is a flexible polymer; and a second tubular layer of a second material, wherein the second material is configured to reduce the permeation of fluid or gas through the tube. In some embodiments, a system may include a degassing system located outside the cavity, wherein the degassing system may be configured to remove gas from the conveying fluid before the conveying fluid enters the tube.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to US Application No. 62 / 978,188, filed February 18, 2020, and US Application No. 62 / 989,464, filed March 13, 2020, which are incorporated herein by reference in their entirety. Technical Field

[0003] This article describes a system for fluid transport within a charged particle beam system, and more particularly, a system for inspecting charged particle beams. Background Technology

[0004] In the manufacturing process of integrated circuits (ICs), it is essential to inspect both completed and unfinished circuit components to ensure they are manufactured according to the design and free of defects. Inspection systems using optical microscopes typically have a resolution as low as a few hundred nanometers; and this resolution is limited by the wavelength of light. As the physical dimensions of IC components continue to shrink to below 100 nanometers or even below 10 nanometers, inspection systems with higher resolution than those using optical microscopes are required.

[0005] Charged particle (electron) beam microscopy (such as scanning electron microscopy (SEM) or transmission electron microscopy (TEM)) with resolutions down to less than nanometers is used as a practical tool for inspecting IC components with feature sizes smaller than 100 nanometers. Using SEM, electrons from a single primary electron beam or multiple primary electron beams can be focused onto a location of interest on the wafer being inspected. The primary electrons interact with the wafer and can be backscattered or cause the wafer to emit secondary electrons. The intensity of the electron beam, including both backscattered and secondary electrons, can vary based on the properties of the wafer's internal and external structures, thereby indicating the presence of defects in the wafer. Summary of the Invention

[0006] This disclosure provides embodiments of apparatus, systems, and methods for delivering water to a stage in a charged particle beam system. In some embodiments, the stage may be configured to hold a wafer; a cavity may be configured to house the stage; and a tube may be disposed within the cavity to deliver fluid between the stage and the outside of the cavity, wherein the tube comprises a first tubular layer of a first material, wherein the first material is a flexible polymer; and a second tubular layer of a second material, wherein the second material is configured to reduce the permeation of fluid or gas through the tube.

[0007] In some embodiments, the tube may be configured to be disposed within a vacuum chamber to transfer fluid between the stage and the outside of the vacuum chamber, wherein the tube may include a first tubular layer of a first material, wherein the first material is a flexible polymer; and a second tubular layer of a second material, wherein the second material is configured to reduce the permeation of fluid or gas through the tube.

[0008] In some embodiments, a method for forming a tube within a vacuum chamber can be provided to transfer fluid between a stage and the outside of the vacuum chamber. The method may include forming a first tubular layer of a first material, wherein the first material is a flexible polymer; forming a second tubular layer of a second material over the first tubular layer, wherein the second material is configured to reduce the permeation of fluid or gas through the tube; and applying a negative bias voltage to the tube via a conductive structure during plasma deposition of the second tubular layer.

[0009] In some embodiments, a system may include a stage configured to hold a wafer; a cavity configured to receive the stage, wherein the cavity is configured to operate in a vacuum environment; a first tube disposed in the cavity and configured to transfer fluid between the stage and an exterior of the cavity; and a degassing system disposed outside the cavity. The degassing system may include: a housing including a plurality of second tubes, wherein the housing is configured to receive the transfer fluid; and a vacuum system configured to remove gas from the transfer fluid before the transfer fluid enters the first tube. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of an exemplary electron beam inspection (EBI) system according to an embodiment of the present disclosure.

[0011] Figure 2 This is a schematic diagram of an exemplary multi-beam system according to an embodiment of the present disclosure. Figure 1 This is part of an exemplary charged particle beam inspection system.

[0012] Figure 3A This is a schematic diagram of an exemplary fluid transport system according to an embodiment of the present disclosure. Figure 2 It is part of an exemplary multi-beam system.

[0013] Figure 3B This is a schematic diagram of an exemplary fluid transport system according to an embodiment of the present disclosure. Figure 2 It is part of an exemplary multi-beam system.

[0014] Figure 3C This is a schematic diagram of an exemplary degassing system according to an embodiment of the present disclosure. The degassing system is... Figure 3B It is part of an exemplary fluid transport system.

[0015] Figure 3D This is a diagram of a hollow fiber membrane tube according to an embodiment of the present disclosure.

[0016] Figure 4A This is an exemplary graph showing the relationship between time and pressure inside the vacuum chamber.

[0017] Figure 4B This is an exemplary graph showing the relationship between time and pressure inside the vacuum chamber.

[0018] Figure 5 This is a diagram of penetration.

[0019] Figure 6 This is a diagram of a multilayer fluid transfer pipe according to an embodiment of the present disclosure.

[0020] Figure 7 This is a diagram illustrating penetration according to an embodiment of the present disclosure.

[0021] Figure 8 This is an exemplary graph showing the relationship between time and pressure inside the vacuum chamber.

[0022] Figure 9 This is an exemplary process flow diagram of forming a fluid transfer tube according to an embodiment of the present disclosure. Detailed Implementation

[0023] The following description will be given in detail with reference to exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings, wherein the same reference numerals in different drawings denote the same or similar elements unless otherwise stated. The embodiments set forth in the following description of exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with aspects related to the subject matter recited in the appended claims. For example, although some embodiments are described in the context of utilizing electron beams, this disclosure is not limited thereto. Other types of charged particle beams may also be applied similarly. Furthermore, other imaging systems, such as optical imaging, photoelectric detection, X-ray detection, etc., may also be used.

[0024] Electronic devices consist of circuits formed on silicon wafers (called "substrates"). Many circuits can be formed together on the same silicon wafer, called integrated circuits or ICs. These circuits are significantly smaller, allowing more circuits to be assembled on the substrate. For example, the IC chip in a smartphone can be as small as a thumbnail, yet still contain over 2 billion transistors, each smaller than 1 / 1000th the size of a human hair.

[0025] Manufacturing these extremely small ICs is a highly complex, time-consuming, and expensive process, typically involving hundreds of individual steps. Even an error in one step can lead to a defect in the finished IC, rendering it useless. Therefore, one goal of the manufacturing process is to avoid such defects in order to maximize the number of functional ICs manufactured in the process, i.e., to improve the overall yield of the process.

[0026] One way to improve yield is to monitor the chip manufacturing process to ensure it produces a sufficient number of functional integrated circuits. One method of monitoring this process is to inspect the chip circuit structure at each stage of its formation. This can be done using a scanning electron microscope (SEM). SEM can be used to image these extremely small structures, essentially taking "photographs" of the wafer structure. The images can be used to determine if the structure is formed correctly and in the correct location. If a defect is found, the process can be adjusted to make that defect less likely to recur.

[0027] A SEM works similarly to a camera. A camera takes a picture by receiving and recording the brightness and color of light reflected or emitted from a person or object. A SEM takes a "picture" by receiving and recording the energy or quantity of electrons reflected or emitted from a structure. Before taking such a "picture," an electron beam can be supplied to the structure, and as electrons are reflected or emitted from the structure ("emission"), the SEM's detector can receive and record the energy or quantity of these electrons to generate an image. To take such "pictures," some SEMs use a single electron beam (called a "single-beam SEM"), while others use multiple electron beams (called a "multi-beam SEM") to take multiple "pictures" of the wafer. By using multiple electron beams, the SEM can supply more electron beams to the structure to obtain those multiple "pictures," thus allowing more electrons to be emitted from the structure. Accordingly, the detector can receive more emitted electrons simultaneously and generate images of the wafer structure with greater efficiency and faster speed.

[0028] Inspection involves moving a stage that holds the wafer within a vacuum chamber. However, the motors used to move the stage typically dissipate a significant amount of heat. Prolonged exposure to overheating can cause the wafer to expand, resulting in structural drift away from the target location. This thermal drift can be fatal when manufacturing computer chips or locating defects on wafers. Even slight temperature changes can cause the region of interest to drift rapidly out of the SEM image's field of view, making image acquisition and data analysis challenging and adversely affecting production volume and inspection yield. Furthermore, heat exposure to adjacent optoelectronic components (such as position sensors, mirrors, motors, etc.) can lead to stage positioning errors and beam placement accuracy errors.

[0029] SEM can operate in a vacuum chamber environment. However, when SEM is being prepared for or operating in a vacuum environment, water vapor or air molecules may leak into the vacuum chamber from other system components, with potentially undesirable results for several reasons. One reason is that leaks may cause the vacuum chamber to take longer to reach the predetermined pressure before a wafer inspection can occur, thus reducing throughput or even preventing the vacuum chamber from reaching the predetermined pressure. For example, in a vacuum environment, water vapor or air molecules may leak into the vacuum chamber from the fluid delivery pipes used for the cooling stage. When water vapor or air molecules leak into the vacuum chamber, the pressure inside may increase, preventing the vacuum chamber from reaching the predetermined pressure required for inspection. This extended time to reach the predetermined pressure (e.g., evacuation time) can reduce system availability.

[0030] Furthermore, water vapor and air molecules can reduce the lifespan of the inspection system due to components sensitive to these contaminants (e.g., pure aluminum components, high-voltage components, charged particle source components, etc.). Therefore, the ability to prevent water vapor and air molecules from entering the vacuum chamber is crucial for improving the throughput and lifespan of the inspection system. The material selection for the fluid delivery tubes is critical for maintaining fluid and gas balance. The fluid delivery tubes should also be flexible to accommodate the moving stage while preventing any water vapor or gas molecules from escaping into the vacuum chamber. In some embodiments, a degassing system can be used to remove dissolved gases from the fluid before it enters one or more tubes within the vacuum chamber, thereby helping to minimize gas leakage into the vacuum chamber.

[0031] This disclosure particularly describes methods and systems for providing flexible fluid delivery tubes to cool a wafer stage while retaining the delivered fluid and gas. This disclosure also particularly describes methods and systems for providing a degassing system outside a vacuum chamber to remove gas from the fluid before it enters one or more tubes within the vacuum chamber. In some embodiments, the degassing system may be disposed inside the vacuum chamber. In some embodiments, the inspection system may include a stage configured to hold a wafer, a vacuum chamber housing the stage, and a plurality of tubes within the chamber that deliver water or other fluids or gases between the stage and the outside of the chamber to a fluid tank or other component inside or outside the system. In some embodiments, each tube may include a flexible polymer substrate coated with an inorganic or metallic material. During plasma deposition, a negative bias may be applied to the flexible polymer substrate to accelerate coating ions, allowing the coating ions to penetrate into the top layer of the flexible polymer substrate, thereby improving the retention force on the delivered fluid. In some embodiments, each tube may include a combination of hydrophobic or hydrophilic materials, thereby retaining water vapor and gas in the fluid. In some embodiments, a multi-beam inspection system may be used. In some embodiments, the degassing system may be disposed outside the vacuum chamber. The degassing system may include a vacuum pump system configured to remove gas from a fluid before it enters one or more tubes within a vacuum chamber. As described above, the degassing system can be used in conjunction with a single-layer tube or a multi-layer tube within a vacuum chamber. The inspection system can be adapted for a variety of applications that optimize the throughput of the inspection system.

[0032] For clarity, the relative dimensions of the parts in the accompanying drawings may be exaggerated. In the following description of the drawings, the same or similar reference numerals denote the same or similar parts or entities, and only the differences between the various embodiments are described.

[0033] Unless otherwise stated, the term "or" as used herein includes all possible combinations, unless it is impractical. For example, if a statement component may include A or B, then unless otherwise specified or impractical, the component may include A or B, or A and B. As a second example, if a statement component may include A, B, or C, then unless otherwise specified or impractical, the component may include A, or B, or C, or A and B, or A and C, or B and C, or A and B and C.

[0034] Figure 1 An exemplary electron beam inspection (EBI) system 100 according to an embodiment of this disclosure is shown. The EBI system 100 can be used for imaging. Figure 1As shown, the EBI system 100 includes a main cavity 101, a loading / locking cavity 102, an electron beam tool 104, and an equipment front-end module (EFEM) 106. The electron beam tool 104 is located within the main cavity 101. The EFEM 106 includes a first loading port 106a and a second loading port 106b. The EFEM 106 may include one or more additional loading ports. The first loading port 106a and the second loading port 106b receive wafer front-open transfer cassettes (FOUPs) containing wafers to be inspected (e.g., semiconductor wafers or wafers made of other materials (one or more)) or samples (wafers and samples are interchangeable). A "batch" is a group of wafers that can be loaded together for processing.

[0035] One or more robotic arms (not shown) in EFEM 106 can transport the wafer to loading / locking chamber 102. Loading / locking chamber 102 is connected to a loading / locking vacuum pump system (not shown) that removes gas molecules from loading / locking chamber 102 to achieve a first pressure below atmospheric pressure. After reaching the first pressure, one or more robotic arms (not shown) can transport the wafer from loading / locking chamber 102 to main chamber 101. Main chamber 101 is connected to a main chamber vacuum pump system (not shown) that removes gas molecules from main chamber 101 to achieve a second pressure below the first pressure. After reaching the second pressure, the wafer is inspected by an electron beam tool 104. Electron beam tool 104 can be a single-beam system or a multi-beam system.

[0036] Controller 109 is electrically connected to electron beam tool 104. Controller 109 may be a computer configured to perform various controls of EBI system 100. Although controller 109 is... Figure 1 The controller 109 is shown as being located outside the structure comprising the main cavity 101, the loading / locking cavity 102, and the EFEM 106, but it is understood that the controller 109 may also be part of the structure.

[0037] In some embodiments, controller 109 may include one or more processors (not shown). A processor may be a general-purpose or special-purpose electronic device capable of manipulating or processing information. For example, a processor may include any number of central processing units (or “CPU”), graphics processing units (or “GPU”), optical processors, programmable logic controllers, microcontrollers, microprocessors, digital signal processors, intellectual property (IP) cores, programmable logic arrays (PLAs), programmable array logic (PALs), general-purpose array logic (GALs), complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), system-on-a-chip (SoCs), application-specific integrated circuits (ASICs), and any combination of any type of circuitry capable of data processing. A processor may also be a virtual processor, including one or more processors distributed across multiple machines or devices coupled via a network.

[0038] In some embodiments, controller 109 may also include one or more memories (not shown). Memory can be a general-purpose or special-purpose electronic device capable of storing code and data accessible by a processor (e.g., via a bus). For example, memory may include any number of random access memory (RAM), read-only memory (ROM), optical disc, magnetic disk, hard disk, solid-state drive, flash drive, secure digital card (SD card), memory stick, compact flash (CF) card, or any combination of any type of storage device. Code may include an operating system (OS) and one or more applications (or “apps”) for a specific task. Memory may also be virtual memory, including one or more memories distributed across multiple machines or devices coupled via a network.

[0039] Now for reference Figure 2 , Figure 2 This is a schematic diagram of an exemplary electron beam tool 104 according to an embodiment of the present disclosure, the electron beam tool 104 including as... Figure 1 The electron beam tool 104 is a multi-beam inspection tool that is part of the EBI system 100. In some embodiments, the electron beam tool 104 can operate as a single-beam inspection tool. Figure 1This is part of the EBI system 100. The multi-beam electron beam tool 104 (also referred to herein as device 104) includes an electron source 201, a coulomb aperture plate (or “gun-hole plate”) 271, a condenser lens 210, a source conversion unit 220, a primary projection system 230, a stage 209, and a sample holder 207 supported by the stage 209 to hold a sample 208 (e.g., a wafer or photomask) to be inspected. The multi-beam electron beam tool 104 may also include a secondary projection system 250 and an electronic inspection device 240. The primary projection system 230 may include an objective lens 231. The electronic inspection device 240 may include multiple inspection elements 241, 242, and 243. A beam splitter 233 and a deflection scanning unit 232 may be disposed within the primary projection system 230.

[0040] The electronic source 201, coulomb aperture plate 271, condenser lens 210, source conversion unit 220, beam splitter 233, deflection scanning unit 232, and primary projection system 230 can be aligned with the main optical axis 204 of device 104. The secondary projection system 250 and electronic detection device 240 can be aligned with the secondary optical axis 251 of device 104.

[0041] The electron source 201 may include a cathode (not shown) and an extractor or anode (not shown), wherein, during operation, the electron source 201 is configured to emit primary electrons from the cathode, and the primary electrons are extracted or accelerated by the extractor and / or the anode to form a primary electron beam 202, which in turn forms a primary beam crossover (virtual or real) 203. The primary electron beam 202 can be considered as being emitted from the primary beam crossover 203.

[0042] Source conversion unit 220 may include an imaging element array (not shown), an aberration compensator array (not shown), a beam confinement aperture array (not shown), and a pre-bent micro-deflector array (not shown). In some embodiments, the pre-bent micro-deflector array deflects a plurality of primary sub-beams 211, 212, 213 of the primary electron beam 202 to allow them to pass normally into the beam confinement aperture array, the imaging element array, and the aberration compensator array. In some embodiments, device 104 may operate as a single-beam system to generate a single primary sub-beam. In some embodiments, condenser lens 210 is designed to focus the primary electron beam 202 into a parallel beam and incident perpendicularly onto source conversion unit 220. The imaging element array may include a plurality of micro-deflectors or microlenses to influence the plurality of primary sub-beams 211, 212, 213 of the primary electron beam 202 and form a plurality of parallel images (virtual or real) of the primary beam intersection 203, each of the primary sub-beams 211, 212, and 213 corresponding to one parallel image. In some embodiments, the aberration compensator array may include a field curvature compensator array (not shown) and an astigmatism compensator array (not shown). The field curvature compensator array may include a plurality of microlenses to compensate for field curvature aberrations of the primary sub-bundles 211, 212, and 213. The astigmatism compensator array may include a plurality of micro-astigmatism correction devices to compensate for astigmatic aberrations of the primary sub-bundles 211, 212, and 213. The bundle-limiting aperture array may be configured to limit the diameter of each of the primary sub-bundles 211, 212, and 213. Figure 2 Three primary sub-bundles 211, 212, and 213 are shown as examples, and it can be understood that the source conversion unit 220 can be configured to form any number of primary sub-bundles. The controller 109 can be connected to... Figure 1 Various components of the EBI system 100, such as the source conversion unit 220, the electronic detection device 240, the primary projection system 230, or the motorized stage 209. In some embodiments, as explained in further detail below, the controller 109 can perform various image and signal processing functions. The controller 109 can also generate various control signals to manage the operation of the charged particle beam inspection system.

[0043] Condensing lens 210 is configured to focus primary electron beam 202. Condensing lens 210 can also be configured to adjust the current of primary sub-beams 211, 212, and 213 downstream of source conversion unit 220 by changing the focusing capability of condensing lens 210. Alternatively, the current can be changed by changing the radial dimension of the beam-limiting apertures in the beam-limiting aperture array corresponding to each primary sub-beam. The current can be changed by changing both the radial dimension of the beam-limiting apertures and the focusing capability of condensing lens 210. Condensing lens 210 can be an adjustable condensing lens and can be configured to have its first principal plane position movable. The adjustable condensing lens can be configured to be magnetic, thereby allowing off-axis sub-beams 212 and 213 to illuminate source conversion unit 220 at a rotational angle. The rotational angle changes with the focusing capability or position of the first principal plane of the adjustable condensing lens. Condensing lens 210 can be an anti-rotation condensing lens and can be configured to maintain a constant rotational angle while the focusing capability of condensing lens 210 changes. In some embodiments, the condenser lens 210 may be an adjustable anti-rotation condenser lens, wherein the rotation angle remains constant when its focusing capability and the position of the first principal plane change.

[0044] Objective lens 231 can be configured to focus sub-beams 211, 212, and 213 onto sample 208 for examination, and in the current embodiment, three detection points 221, 222, and 223 can be formed on the surface of sample 208. Coulomb aperture plate 271 is configured in operation to block peripheral electrons of primary electron beam 202 to reduce the Coulomb effect. The Coulomb effect may enlarge the size of each detection point 221, 222, and 223 of primary sub-beams 211, 212, and 213, thereby reducing the examination resolution.

[0045] Beam separator 233 can be, for example, a Wien filter, including an electrostatic deflector that generates electrostatic dipole fields and magnetic dipole fields. Figure 2 (Not shown in the diagram). In operation, the beam splitter 233 can be configured to apply an electrostatic force to the individual electrons of the primary sub-bundles 211, 212, and 213 via an electrostatic dipole field. The electrostatic force is equal in magnitude but opposite in direction to the magnetic force applied to the individual electrons by the magnetic dipole field of the beam splitter 233. Therefore, the primary sub-bundles 211, 212, and 213 can pass through the beam splitter 233 at least substantially in a straight line with at least substantially zero deflection angle.

[0046] Deflection scanning unit 232 is configured in operation to deflect primary sub-beams 211, 212, and 213 to scan detector points 221, 222, and 223 on various scanning regions in a portion of the surface of sample 208. In response to the primary sub-beams 211, 212, and 213 incident on detector points 221, 222, and 223 of sample 208, electrons are emitted from sample 208, generating three secondary electron beams 261, 262, and 263. Each of the secondary electron beams 261, 262, and 263 typically comprises secondary electrons (electron energy ≤ 50 eV) and backscattered electrons (electron energy between 50 eV and the landing energy of the primary sub-beams 211, 212, and 213). Beam splitter 233 is configured to deflect the secondary electron beams 261, 262, and 263 toward secondary projection system 250. The secondary projection system 250 then focuses the secondary electron beams 261, 262, and 263 onto the detection elements 241, 242, and 243 of the electron detection device 240. The detection elements 241, 242, and 243 are arranged to detect the corresponding secondary electron beams 261, 262, and 263 and generate corresponding signals, which are sent to the controller 109 or a signal processing system (not shown), for example, to construct an image of the corresponding scan area of ​​the sample 208.

[0047] In some embodiments, detection elements 241, 242, and 243 detect corresponding secondary electron beams 261, 262, and 263, respectively, and generate corresponding intensity signal outputs (not shown) to an image processing system (e.g., controller 109). In some embodiments, each detection element 241, 242, and 243 may include one or more pixels. The intensity signal output of the detection element may be the sum of signals generated by all pixels within the detection element.

[0048] In some embodiments, controller 109 may include an image processing system comprising an image acquirer (not shown) and a memory (not shown). The image acquirer may include one or more processors. For example, the image acquirer may include a computer, server, host, terminal, personal computer, any kind of mobile computing device, or a combination thereof. The image acquirer may be communicatively coupled to electronic detection device 240 of device 104 via a medium, including electrical conductors, optical fibers, portable storage media, IR, Bluetooth, the Internet, wireless networks, radio, or a combination thereof. In some embodiments, the image acquirer may receive signals from electronic detection device 240 and may construct an image. Thus, the image acquirer may acquire an image of sample 208. The image acquirer may also perform various post-processing functions, such as generating contours, overlaying indicators on the acquired image, etc. The image acquirer may be configured to perform brightness and contrast adjustments on the acquired image, etc. In some embodiments, the memory may be a storage medium, such as a hard disk, flash drive, cloud storage, random access memory (RAM), other types of computer-readable storage, etc. The memory may be coupled to the image acquirer and may be used to save scanned raw image data as raw images and post-processed images.

[0049] In some embodiments, the image acquirer may acquire one or more images of a sample based on an imaging signal received from the electronic detection device 240. The imaging signal may correspond to a scanning operation for performing charged particle imaging. The acquired image may be a single image comprising multiple imaging regions. The single image may be stored in memory. The single image may be an original image that can be divided into multiple regions. Each region may include an imaging region containing features of sample 208. The acquired images may include multiple images of a single imaging region of sample 208 sampled multiple times over a time series. The multiple images may be stored in memory. In some embodiments, the controller 109 may be configured to perform image processing steps on multiple images of the same location of sample 208.

[0050] In some embodiments, controller 109 may include measurement circuitry (e.g., an analog-to-digital converter) to obtain the distribution of detected secondary electrons. Electron distribution data collected during the detection time window, combined with corresponding scan path data of each of the primary sub-beams 211, 212, and 213 incident on the wafer surface, can be used to reconstruct an image of the structure of the wafer under inspection. The reconstructed image can be used to reveal various features of the internal or external structure of sample 208, and thereby can be used to reveal any defects that may exist in the wafer.

[0051] In some embodiments, the controller 109 may control the stage 209 to move the sample 208 during examination. In some embodiments, the controller 109 may enable the stage 209 to move the sample 208 continuously in one direction at a constant speed. In other embodiments, the controller 109 may enable the stage 209 to change the speed of movement of the sample 208 over time according to the steps of the scanning process.

[0052] although Figure 2 The apparatus 104 is shown to use three primary electron beams, but it should be understood that the apparatus 104 may also use two or more primary electron beams. This disclosure does not limit the number of primary electron beams used in the apparatus 104. In some embodiments, the apparatus 104 may be a SEM for photolithography.

[0053] Compared to a single charged particle beam imaging system (“single-beam system”), multiple charged particle beam imaging systems (“multi-beam system”) can be designed to optimize throughput for different scanning modes. Embodiments of this disclosure provide a multi-beam system with the ability to optimize throughput for different scanning modes by using beam arrays with different geometries to accommodate different throughput and resolution requirements.

[0054] A non-transitory computer-readable medium may be provided, which stores information for a processor (e.g., Figures 1 to 2 The controller 109 (processor) executes instructions to perform image processing, data processing, subbeam scanning, database management, graphic display, operation of charged particle beam devices or other imaging apparatuses, etc. Common forms of non-transient media include, for example, floppy disks, flexible disks, hard disks, solid-state drives, magnetic tape or any other magnetic data storage media, CD-ROMs, any other optical data storage media, any physical media with a perforated pattern, RAM, PROMs and EPROMs, FLASH-EPROMs or any other flash memory, NVRAM, caches, registers, any other memory chips or cartridges and their networking versions.

[0055] Now for reference Figure 3A , Figure 3A This is a schematic diagram of an exemplary fluid transfer system 300A according to an embodiment of the present disclosure. Figure 2 This is part of an exemplary multi-beam system. The fluid delivery system 300A may include a fluid tank 301 that delivers fluids (e.g., water, ethylene glycol, mixtures of water and ethylene glycol, etc.) to or outside an atmospheric fluid bath 303. Figure 2 Components of an exemplary multi-beam system or with Figure 2The exemplary multi-beam system is separate. Fluid tank 301 may include a heat exchanger, pump, valve, or other components that can be used to supply fluid to wafer stage 307 to cool wafer stage 307 or hold wafers on wafer stage 307. Wafer stage 307 and Figure 2 The motor platform 209 can be the same component.

[0056] Fluid tank 301 can transfer fluid from fluid bath 303 to rigid tube 313 (e.g., metal tube). Rigid tube 313 can be connected to outer flexible tube 315 (e.g., polyurethane tube), which can then transfer fluid to vacuum chamber 305, or to additional systems or components 309 inside or outside the system. Fluid can be transferred from outer flexible tube 315 to inner flexible tube 317 inside vacuum chamber 305. Wafer stage 307 can be cooled by the fluid transferred through inner flexible tube 317. Therefore, fluid can be continuously circulated through inner flexible tube 317, to outer flexible tube 315 and rigid tube 313 outside chamber 305, and then back to fluid tank 301 until cooling is complete and evacuation begins.

[0057] Due to the low permeability of the rigid tube 313, the fluid transported through the rigid tube 313 can remain within it. However, due to the presence of air molecules (e.g., O2, N2, etc.) in the atmospheric fluid bath 303, these air molecules can permeate into the outer flexible tube 315 and thus enter the vacuum chamber 305 through the inner flexible tube 317. Additionally, due to the porosity and crystalline structure of the outer flexible tube 315, air molecules 311 can permeate into it and thus enter the vacuum chamber 305 through the inner flexible tube 317. In ambient and low-pressure systems, the inner flexible tube 317 can be made of polytetrafluoroethylene (PTFE). However, PTFE may not be preferred in high-vacuum and ultra-high-vacuum applications, such as some embodiments for rapid wafer stage water cooling in multi-beam systems. PTFE exhibits high permeability to air molecules due to its porosity and crystalline structure, especially when a pressure gradient is established between the interior of the inner flexible tube 317 and the vacuum chamber 305. Therefore, when PTFE is used in the inner flexible tube 317 in high vacuum applications, air molecules can permeate into the vacuum chamber 305.

[0058] Now for reference Figure 3B , Figure 3B This is a schematic diagram of an exemplary fluid transfer system 300B according to an embodiment of the present disclosure. Figure 2 This is part of an exemplary multi-beam system. The fluid transport system 300B may include components from the above-described... Figure 3A The components of the 300A fluid transfer system operate in a similar manner.

[0059] The fluid delivery system 300B may include a degassing system 320 disposed outside the vacuum chamber 305. In some embodiments, the degassing system 320 may be disposed inside the vacuum chamber 305. The degassing system 320 may be configured to receive the delivery fluid from the outer flexible tube 315 and remove air molecules 321 from the delivery fluid before the delivery fluid enters the inner flexible tube 317 within the vacuum chamber 305. In some embodiments, a single degassing system may be disposed outside the fluid tank 301. In some embodiments, multiple degassing systems may be provided, with each of the multiple outer flexible tubes 315 corresponding to one degassing system. In some high vacuum and ultra-high vacuum applications, such as rapid wafer stage water cooling for multi-beam systems, the inner flexible tube 317 may be made of PTFE. Because the degassing system 320 can remove gases (e.g., O2, N2, etc.) from the delivery fluid before the delivery fluid enters the vacuum chamber 305, the high permeability of air molecules in PTFE may prevent gas leakage into the chamber 305. In some embodiments, the inner flexible tube 317 may be a multilayer fluid delivery tube (e.g., Figure 6 (600 tubes).

[0060] Now for reference Figure 3C , Figure 3C This is a schematic diagram of an exemplary degassing system 320 according to an embodiment of the present disclosure. Figure 3B Part of the exemplary fluid transport system 300B, and also referenced to Figure 3D , Figure 3D This is an illustration of a hollow fiber membrane tube 324 according to an embodiment of the present disclosure. Figure 3C As shown, the degassing system 320 may include a housing 322, which may include a plurality of hollow fiber membrane tubes 324 (e.g., polypropylene tubes), a collection tube 323, and a baffle 327. The plurality of hollow fiber membrane tubes 324 can provide a large surface area for liquid-gas contact within the housing 322. Transfer fluid may flow from an outer flexible tube 315 into the fluid inlet 330 of the housing 322. The baffle 327 can force the transfer fluid to flow radially over the hollow fiber membrane tubes 324 to maximize the membrane surface area in contact with the transfer fluid. The transfer fluid may flow through the collection tube 323 and around the outer surface of the hollow fiber membrane tubes 324. The transfer fluid may flow through the collection tube 323 to the outside of the housing 322 and flow into the cavity 305 from the fluid outlet 331.

[0061] The degassing system 320 may also include a vacuum pump system 333. The vacuum pump system 333 may be connected to the housing 322 via a gas outlet 332, allowing gas to flow from inside the hollow fiber membrane tube 324 to the gas outlet 332. For example, the vacuum pump system 333 may be operated such that gas within the hollow fiber membrane tube 324 flows in a countercurrent direction. This countercurrent flow of gas within the hollow fiber membrane tube 324 can counteract the balance between the liquid and gas phases of the transport fluid, creating a pressure gradient between the inside and outside of the hollow fiber membrane tube 324, wherein the inside of the hollow fiber membrane tube 324 may have a low pressure (or low gas concentration), and the outside of the hollow fiber membrane tube 324 may have a high pressure (or high gas concentration). In some embodiments, the hollow fiber membrane tube 324 may be configured to extend in a direction perpendicular to the length of the housing 322, eliminating the need for a baffle 327 in the degassing system 320. In some embodiments, a stripping gas can be applied to an additional inlet of the housing 322, allowing the stripping gas to flow inside the hollow fiber membrane tube 324 to improve the gas removal efficiency for a specific gas type. For example, applying N2 stripping gas can improve the efficiency of removing O2 from the transport fluid.

[0062] like Figure 3D As shown, due to the pressure gradient (or gas concentration gradient) formed between the inside and outside of the hollow fiber membrane tube 324, the gas 325 dissolved in the transport fluid 326 can be transported from the outside (high-pressure side) of the hollow fiber membrane tube 324 to the inside (low-pressure side). The gas 325 (e.g., air molecules 321) can continue through the hollow fiber membrane tube 324 toward the vacuum pump system 333 (low-pressure side) to the transported gas outlet 332.

[0063] In some embodiments, the vacuum pump system 333 may be a vacuum pump. In some embodiments, the vacuum pump system 333 may be an air-driven vacuum pump. When the vacuum pump system 333 is an air-driven vacuum pump, the vacuum pump system 333 can compress air such that the compressed air flows through the opening of the gas outlet 332. The air-driven vacuum pump can operate according to Bernoulli's principle, such that as the rate of compressed air increases, the pressure of the vacuum pump system 333 decreases, thereby creating a vacuum environment.

[0064] In some embodiments, the degassing system 320 may include multiple degassing systems, with each outer flexible tube 315 corresponding to one degassing system, to improve the efficiency of removing gas from the transport fluid. In some embodiments, the flow rate of the transport fluid may be adjusted to reduce the flow rate, thereby removing more dissolved gas from the transport fluid. Reducing the flow rate of the transport fluid allows the transport fluid to remain in the degassing system 320 for a longer time, thereby increasing the amount of dissolved gas removed from the transport fluid.

[0065] Now for reference Figure 4A , Figure 4A It is time and vacuum cavity (e.g.) Figure 3A An exemplary relationship curve between the pressures within the vacuum chamber 305. Figure 4A As shown, the horizontal axis represents time, and the vertical axis represents the pressure inside the vacuum chamber. The 40-hour timeframe 411 indicates the time during which the system, as a test, could stop the circulating water flow, indicating the presence of static water within the PTFE fluid delivery tube. The figure shows the total pressure 401 inside the vacuum chamber, and the partial pressures of H₂O (water) 403, N₂ (air component) 405, O₂ (air component) 407, and Ar (air component) 409. It should be noted that under actual conditions, the system may not stop the circulating water flow.

[0066] like Figure 4A As shown, at time 411, the water partial pressure 403 remains constant, while the partial pressures of nitrogen 405, oxygen 407, and argon 409 decrease. The decrease in the partial pressures of nitrogen, oxygen, and argon at time 411 can represent a decrease in the number of air molecules escaping the PTFE fluid delivery tube and entering the surrounding vacuum chamber, because at time 411, the number of air molecules entering and exiting the fluid chamber (e.g., ) increases significantly. Figure 3A The water circulation in the fluid tank 301 has been shut off. Since air molecules can leave the system with the water, and no new air molecules can enter the system after the water circulation is shut off, the closed water circulation results in fewer air molecules escaping from the PTFE fluid transfer pipe. Therefore, under the pressure gradient, air molecules can penetrate the high permeability of PTFE from... Figure 4A This can be seen from the text.

[0067] Now for reference Figure 4B , Figure 4B It is time and vacuum cavity (e.g.) Figure 3B An exemplary relationship graph between pressures within a vacuum chamber 305. The system may include a fluid chamber (e.g., Figure 3B The degassing system between the fluid tank 301 and the vacuum chamber (e.g., the degassing system between the fluid tank 301 and the vacuum chamber) Figure 3B The degassing system 320 may include an external flexible tube (e.g., a tube located between the degassing system and the vacuum chamber). Figure 3B External flexible tube 315). For example... Figure 4B As shown, the horizontal axis represents time, and the vertical axis represents the pressure inside the vacuum chamber. Time span 431 indicates the time span during which the system under test can stop circulating water flow, indicating the presence of static water within the PTFE fluid delivery tube. Time span 432 indicates the time span during which the system can start circulating water flow. Time span 433 indicates that the system can use a degassing system (e.g., ...) while circulating water. Figure 3BThe time span of the degassing system 320 is shown in the figure. The total pressure 421 in the vacuum chamber, and the partial pressures of N2 (air component) 425, O2 (air component) 427 and Ar (air component) 428 are also shown. It should be noted that under actual conditions, the system may not stop circulating water flow.

[0068] like Figure 4B As shown, when the degassing system is used between time spans 432 and 433, the total pressure 421 and partial pressures 425, 427, and 428 decrease. The decrease in nitrogen, oxygen, and argon pressures at the beginning of time span 433 can indicate a decrease in the number of air molecules entering the vacuum chamber, because at the beginning of time span 433, the degassing system can remove gases from the transport fluid before it enters the vacuum chamber.

[0069] like Figure 4B As shown, the total pressure 421 can have similar values ​​during time spans 431 and 433. These similar total pressure values ​​can indicate that a considerable number of gas molecules did not enter the vacuum chamber via the outer flexible tube.

[0070] Now for reference Figure 5 , Figure 5 This is an illustration of permeation according to an embodiment of the present disclosure. Depending on the properties of the polymer (e.g., chemical composition, crystallinity, molecular weight, etc.) and the properties of the fluid (e.g., molecular size, polarity, etc.), the polymer can have varying degrees of fluid (e.g., gas, vapor, liquid, etc.) permeability. Molecular transport through the polymer can be induced by pressure gradients, temperature gradients, concentration gradients, or external force fields. For example, in high or ultra-high vacuum systems (e.g., Figure 3A In the vacuum chamber 305, water and gas molecules emerge from the inner flexible tube (e.g., Figure 3A The transmission from the inner flexible tube (317) to the outer flexible tube can be caused by the pressure or concentration gradient between the inside of the tube and the inside of the vacuum chamber.

[0071] Fluid permeation through a polymer can include three steps: (1) at a higher potential P 高 On the side (e.g., inside the inner flexible tube 317 in Figure 3), molecules 501 or 503 dissolve (are absorbed) into the polymer (e.g. Figure 3A (2) Molecules diffuse in and through the membrane 513 of the inner flexible tube 317; and (3) at a lower potential P 真空 Side (e.g.) Figure 3A In the vacuum chamber 305, the diffusing molecules on the opposite side are released (desorbed) into the fluid. The term "permeation" describes the total mass transfer of the permeate fluid through the membrane, while the term "diffusion" describes the movement of permeate molecules within the membrane bulk.

[0072] The permeability of a fluid through a polymer can depend on the polarity of both the fluid and the polymer. Molecules can contain multiple bonds. When two atoms sharing an electron have equal electronegativity, they can form a nonpolar bond. When two atoms sharing an electron have unequal electronegativity, the atoms share electrons unequally and can form a partial ionic charge. This unequal sharing of electrons creates bond dipoles, where the resulting bond is polar. If the bond dipoles present in a molecule cannot cancel each other out, the molecule is polar. If the bond dipoles present in a molecule can cancel each other out, the molecule is nonpolar. Polar molecules attract and bind to other polar molecules due to their partial charge. Nonpolar molecules remain to form groups with other nonpolar molecules, forming weak bonds, while polar molecules attract other polar molecules. Therefore, polar molecules can easily permeate through polar membranes but not easily through nonpolar membranes. Similarly, nonpolar molecules can easily permeate through nonpolar membranes but not easily through polar membranes.

[0073] For example, molecule 501 can be polar (e.g., water), molecule 503 can be nonpolar (e.g., N2, O2), and polymer film 513 can be nonpolar. Under a pressure gradient P... 高 To P 真空 In the system, polar molecule 501 can be maintained at a high potential P of nonpolar membrane 613. 高 On the other hand, nonpolar molecules 503 can permeate through nonpolar membrane 513.

[0074] For many reasons, vacuum cavities (e.g.) Figure 3A Water vapor and air molecules within the vacuum chamber 305 may be undesirable. One reason is that the pressure within the vacuum chamber may need to reach a predetermined pressure before a wafer inspection can occur. From flexible tubes (e.g., Figure 3A Water vapor and air molecules escaping from the inner flexible tube 317 into the vacuum chamber can increase the pressure within the vacuum chamber, thereby preventing the vacuum chamber from falling to the predetermined pressure required for inspection. The extended time it takes for this system to reach the predetermined pressure (e.g., evacuation time) may reduce system availability, for example, as described below. Figure 8 The comparison curves 801-804A to 801-804B are shown in the figures. Furthermore, water vapor and air molecules can reduce the lifespan of the inspection system due to contaminant-sensitive components (such as pure aluminum components, high-voltage components, and electronic sources). Therefore, the selection of flexible tubing materials is crucial for improving the throughput and lifespan of the inspection system.

[0075] Now for reference Figure 6 , Figure 6 This is an illustration of a multilayer fluid transfer pipe according to an embodiment of the present disclosure. Figure 6 As shown, the fluid transfer pipe 600 (e.g.) Figures 3A to 3B The inner flexible tube 317 may include multiple tubular layers (such as layers 601, 602, or 603). It should be understood that the tube 600 is not limited to the described embodiments, but may include two or more layers (e.g., tubular layers).

[0076] Due to their effective pore permeability, coating flexible polymers with diamond-like carbon (DLC), ionomers, or dense polymers can provide structures that are effectively impermeable to oxygen and water vapor, while maintaining flexibility for rapid wafer stage movement during inspection. Additionally, these coating materials can be designed to improve conductivity or abrasion resistance. For example, some uncoated flexible polymers (e.g., PTFE) can be insulating polymers with high electron affinity, which could lead to electrostatic risks in the system due to high voltages during operation. Effectively reducing the permeability of fluid delivery tubes can improve the system (e.g., Figures 3A to 3B In addition to reducing the permeation of fluids (such as water, air, etc.) from the inside of the tube to the outside of the tube and into the vacuum chamber, the vacuum chamber can also achieve a lower pressure.

[0077] In some embodiments, the tube 600 may comprise only two layers 601 and 602, wherein layer 601 may be polar and layer 602 may be nonpolar. Since water is polar and air molecules are nonpolar, this embodiment may preferably reduce the absorption of water vapor or air molecules by the tube 600. In some embodiments, layer 601 may be nonpolar and layer 602 may be polar. For example, the polar layer may comprise at least one layer of polyvinylidene chloride (PVDC) or ethylene-vinyl alcohol copolymer (EVOH), because PVDC and EVOH are polar molecules with low permeability coefficients to oxygen and water (e.g., 0.00425 to 0.00425-0.57 cm³-mm / m²-d-atm O₂, 0.025-0.913 g-mm / m²-d water for PVDC, and 0.01-0.15 cm³-mm / m²-d-atm O₂, 0.8-2.4 g-mm / m²-d water for EVOH). The nonpolar layer may include at least one layer of PTFE, since PTFE is a nonpolar molecule that has a low permeability coefficient to water (e.g., 0.0045-0.30 g-mm / m2-d water).

[0078] In some embodiments, the tube 600 may include three layers 601-603, wherein layer 601 may be polar, layer 602 may be an adhesive layer, and layer 603 may be non-polar. In some embodiments, layer 601 may be non-polar, while layer 603 may be polar. In some cases, having at least three layers may preferably increase the adhesion between layers 601 and 603, thereby improving the stability of the tube 600 and reducing the permeability of water vapor or air molecules through the tube 600. As mentioned above, water is polar, and air molecules are non-polar. Since PVDC and EVOH are polar molecules, the polar layer may include at least one layer of PVDC or EVOH. The non-polar layer may include at least one layer of PTFE, as PTFE is a non-polar molecule. The adhesive layer may include at least one layer of polyimide.

[0079] In some embodiments, tube 600 may include two layers 601 and 602, wherein 602 coats 601. For example, layer 601 may include at least one flexible polymer substrate (e.g., PTFE, polyethylene terephthalate, etc.), and layer 602 may include a DLC coating, a metal coating (e.g., Cr, Al, etc.), a metal oxide coating (e.g., AlOx), a half-metal oxide coating (e.g., SiOx), or a dense polymer coating (e.g., polyimide / Kapton, polyvinylidene fluoride, etc.). In some cases, this layer construction may preferably reduce molecular diffusion of water vapor or air molecules within and across tube 600. Coating 602 may fill the pores of layer 601, thereby reducing the permeation of water vapor or air molecules across tube 600 during the diffusion phase of permeation. In some embodiments, layer 602 may include a DLC coating or a metal coating, which is applied to layer 601 under a negative bias by inserting a conductive structure (e.g., a wire) into layer 601. A negative bias voltage can be applied during plasma deposition of layer 602 to accelerate ion coating and allow coated ions to penetrate into the top layer of layer 601, thereby blocking gaps and pores in layer 601 and reducing fluid permeability into tube 600. In some embodiments, each DLC coating, metal coating, metal oxide coating, or half-metal oxide coating can have a thickness of 10-50 nm without affecting the mechanical properties of tube 600. In some embodiments, tube 600 may include at least one adhesive layer. In some embodiments, at least one layer of PVDC or EVOH may be located inside or outside layer 601 and coating 602.

[0080] Now for reference Figure 7 , Figure 7 This is an illustration of penetration according to an embodiment of the present disclosure. Figure 5Similarly, the environment can contain polar molecules 701 and nonpolar molecules 703. The polymer film 713 can include two or more layers, including a polar layer 715 and a nonpolar layer 717. Under a pressure gradient P... 高 To P 真空 In the system, nonpolar molecule 703 can be retained in the high potential P of polar layer 715. 高 On the side, polar molecules 701 can permeate through the polar layer 715. However, polar molecules 701 can be retained in the polar layer 715 due to the nonpolar layer 717. Therefore, molecules 701 and 703 can be prevented from escaping to the low potential side P of the film 713. 真空 In some embodiments, a layer comprising nonpolar (or hydrophobic) molecules (e.g., PTFE) may have a water contact angle greater than 90 degrees. In some embodiments, a layer comprising polar (or hydrophilic) molecules (e.g., PVDC, EVOH, etc.) may have a water contact angle less than 90 degrees.

[0081] Reducing the permeation of molecules 701 and 703 (such as water vapor, air molecules, etc.) is important for reducing the risk of vacuum chamber system (e.g.) Figures 3A to 3B The pressure within the vacuum chamber 305 may be advantageous. In systems where no fluid or gas escapes from the fluid delivery tube, the system pressure can increase with the increase of gas molecules in the system (e.g., Figure 8 (Curves 801-804B), so the pressure inside the vacuum chamber can be lower. In systems where no fluid or gas escapes from the fluid delivery tube, the system pressure can decrease as the molecular weight of the gas decreases, so the pressure in the vacuum chamber can reach a lower pressure in a shorter time. Lowering the pressure in the vacuum chamber in a shorter time allows charged particle systems (e.g., Figure 1 The EBI system 100) uses high voltage (e.g.) more quickly. Figure 8 (Line 813), and collect inspection measurements more quickly (e.g. Figure 8 (Line 815). Therefore, reducing the pressure in the vacuum chamber in a shorter time can optimize and extend the life of the inspection system. For example, using a fluid delivery tube to reduce the permeation of water vapor and air molecules into the vacuum chamber can shorten the evacuation time from 40 hours to 16 hours. In addition, using this fluid delivery tube can reduce the final vacuum chamber pressure, thereby extending the life of the inspection system.

[0082] Now for reference Figure 8 , Figure 8 It is time and vacuum cavity (e.g.) Figures 3A to 3B An exemplary relationship curve between the pressures within the vacuum chamber 305. Figure 8As shown, the horizontal axis represents time in hours, and the vertical axis represents the pressure inside the vacuum chamber. Curves 801A, 802A, 803A, and 804A are the pressures inside the vacuum chamber measured when the PTFE tube is used as a flexible tube (e.g., the inner flexible tube 317 in Figure 3) in a vacuum chamber without a degassing system, while curves 801B, 802B, 803B, and 804B are the pressures measured when the multilayer delivery tube (e.g., ...) is used. Figure 6 The fluid transfer tube 600 is a flexible tube used in a vacuum chamber or with a degassing system (e.g., Figure 3B The pressure inside the vacuum chamber is estimated when using the degassing system 320. Curves 801A and 801B represent the total pressure inside the vacuum chamber, curves 802A and 802B represent the water pressure inside the vacuum chamber, curves 803A and 803B represent the nitrogen partial pressure inside the vacuum chamber, and curves 804A and 804B represent the oxygen partial pressure inside the vacuum chamber. As shown by curves 801-804B, in systems using multilayer transfer tubes, the pressure inside the vacuum chamber can be lower because no fluid or gas can escape from the multilayer transfer tubes, allowing the use of a combination of polar and non-polar layers. In systems using single-layer tubes with a degassing system, the pressure inside the vacuum chamber can also be lower because dissolved gases can be removed from the transfer fluid before it enters the vacuum chamber. In systems where no fluid or gas escapes from the multilayer transfer tubes, the pressure inside the vacuum chamber can be lower because the system pressure can increase with the increase in gas molecules in the system, as shown by curves 801-804A. Similarly, in systems where dissolved gases are removed from the transfer fluid before it enters the vacuum chamber, the pressure within the vacuum chamber can be lower. For example, as shown in curves 803A and 804A, gases (e.g., N2, O2, etc.) can escape from flexible tubes using PTFE because PTFE is non-polar when a degassing system is not used. Therefore, as shown in curves 802A and 802B, when using PTFE or multilayer transfer tubes, the water retention of the flexible tubes can be the same due to the non-polar nature of PTFE.

[0083] Line 813 is a charged particle system (e.g.) Figure 1The EBI system 100 can use the maximum pressure available under high pressure. Charged particle systems may require inspections to be performed under high pressure; therefore, the faster the vacuum chamber pressure drops below line 813, the faster the charged particle system can operate under high pressure, thus increasing system throughput. Line 815 is the maximum pressure at which the charged particle system can collect inspection measurements. Multilayer transfer tubes with a combination of polar and non-polar layers, single-layer transfer tubes with a degassing system, or combinations thereof may be desirable because the faster the vacuum chamber pressure drops below line 815, the faster the charged particle system can perform inspections. Therefore, if the vacuum chamber pressure reaches line 815 more quickly, system throughput can be increased. In systems where no fluid or gas escapes from the fluid transfer tube (e.g., curves 801-804B) or enters the vacuum chamber, the vacuum chamber pressure can reach a lower pressure in a shorter time (e.g., approximately 10 hours) because the system pressure can decrease with decreasing gas molecular weight. Therefore, when gas molecules are retained in the fluid delivery tube or removed from the delivery fluid before entering the vacuum chamber, the pressure in the vacuum chamber can be reached in a shorter time (e.g., about 10 hours) compared to a system using conventional piping (e.g., about 40 hours), thus allowing the system to provide higher production rates.

[0084] like Figure 8 As shown, the selection of materials for fluid transfer tubes, preferably those that prevent fluid or gas (e.g., water vapor, air molecules) from escaping into the vacuum chamber, or the use of a degassing system, is important for optimizing and extending the lifespan of the inspection system.

[0085] Now for reference Figure 9 , Figure 9 This is a flowchart of an exemplary method 900 for forming a fluid delivery tube according to an embodiment of the present disclosure.

[0086] In step 901, a first layer of the first material (e.g., Figure 6 Layer 601), formed in the cavity (e.g. Figures 3A-3B The vacuum chamber 305 is used for use in a stage (e.g., Figures 3A-3B A tube (e.g., the inner flexible tube 317 of FIG. 3) for conveying fluid (e.g., water) between the wafer stage 307 and the outside of the cavity, wherein the first material is a flexible polymer. The flexible polymer layer may be non-polar (e.g., PTFE).

[0087] In step 903, forming the tube may further include forming a second layer of a second material on top of the first layer (e.g., Figure 6Layer 602), wherein the second material may include a DLC coating, a metal coating (e.g., Cr, Al, etc.), a metal oxide coating (e.g., AlOx), a half-metal oxide coating (e.g., SiOx), or a dense polymer coating (e.g., polyimide / Kapton, polyvinylidene fluoride, etc.). The second material may be configured to reduce the permeation of fluids (e.g., water) or gases (e.g., N2, O2) through the tube during the molecular diffusion stage by filling the pores of the flexible polymer.

[0088] In step 905, during the plasma deposition of the second layer, a negative bias voltage can be applied to the tube via a conductive structure to accelerate the coating of ions from the second material and allow the coated ions to penetrate into the top layer of the flexible polymer, thereby blocking the gaps and pores of the flexible polymer and reducing the fluid permeability into the tube. Reducing the fluid permeability into the tube prevents, for example, water vapor and air molecules from entering the vacuum chamber. Since the system pressure can be reduced by decreasing the molecular weight of the gas, the vacuum chamber can reach a lower pressure in a shorter time. Reducing the pressure of the vacuum chamber in a shorter time allows charged particle systems (e.g., Figure 1 The EBI system 100 uses high pressure more quickly and collects inspection measurements faster, thereby optimizing the inspection output of the inspection system.

[0089] In step 907, forming the tube may further include forming a third layer of a third material (e.g., on top of the first layer) on the first layer. Figure 6 The third material (layer 603) may include a polar layer (e.g., PVDC, EVOH, etc.). The third layer forming the polar third material can reduce the absorption of, for example, water vapor or air molecules by the tube, thereby further reducing the permeation of water vapor or air molecules into the tube and reducing the pressure of the vacuum chamber in a shorter time.

[0090] The embodiments may be further described using the following terms:

[0091] 1. A system comprising:

[0092] The platform is configured as a fixed chip;

[0093] A cavity, configured to house the stage, and wherein the cavity is configured to operate in a vacuum environment; and

[0094] A tube, disposed within the cavity and configured to convey fluid between the stage and the outside of the cavity, wherein the tube comprises:

[0095] A first tubular layer of a first material, wherein the first material is a flexible polymer; and

[0096] A second tubular layer of a second material, wherein the second material is configured to reduce the permeation of fluid or gas through the tube.

[0097] 2. The system according to Clause 1, wherein the flexible polymer comprises polytetrafluoroethylene (PTFE).

[0098] 3. The system according to Clause 1, wherein the flexible polymer comprises polyethylene terephthalate (PET).

[0099] 4. The system according to any one of clauses 1 to 3, wherein the second tubular layer coats the first tubular layer.

[0100] 5. The system according to any one of clauses 1 to 4, wherein the second material is diamond-like carbon.

[0101] 6. The system according to any one of clauses 1 to 4, wherein the second material is a metal oxide.

[0102] 7. The system according to Clause 6, wherein the metal oxide is aluminum oxide.

[0103] 8. The system according to any one of clauses 1 to 4, wherein the second material is a metal.

[0104] 9. The system according to Clause 8, wherein the metal is aluminum.

[0105] 10. The system according to Clause 8, wherein the metal is chromium.

[0106] 11. The system according to any one of clauses 1 to 4, wherein the second material is a half-metal oxide.

[0107] 12. The system according to Clause 11, wherein the semi-metal oxide is silicon oxide.

[0108] 13. The system according to any one of clauses 1 to 4, wherein the second material is a polymer.

[0109] 14. The system according to Clause 13, wherein the polymer is polyimide.

[0110] 15. The system according to Clause 13, wherein the polymer is at least one of polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), or ethylene-vinyl alcohol copolymer (EVOH).

[0111] 16. The system according to any one of clauses 5 to 12, wherein the thickness of the second tubular layer is 10 to 50 nanometers.

[0112] 17. The system according to any one of clauses 1, 2 or 4 to 16, wherein the tube further comprises a third tubular layer of a third material, wherein the third material is configured to reduce gas permeation through the tube.

[0113] 18. The system according to Clause 17, wherein the third tubular layer is located above the second tubular layer.

[0114] 19. The system according to Clause 17, wherein the first tubular layer is located above the third tubular layer.

[0115] 20. The system according to any one of clauses 1, 2 or 4 to 19, wherein the first tubular layer comprises a fluid contact angle greater than 90 degrees.

[0116] 21. The system according to any one of clauses 1, 2 or 4 to 20, wherein the third tubular layer comprises a fluid contact angle of less than 90 degrees.

[0117] 22. The system according to any one of clauses 1 to 21, wherein the tube further comprises an adhesive layer.

[0118] 23. The system according to claims 1 to 22 further includes an adhesive layer located between each of the first tubular layer, the second tubular layer, or the third tubular layer.

[0119] 24. The system according to any one of clauses 22 or 23, wherein the adhesive layer comprises polyimide.

[0120] 25. The system according to any one of clauses 17 to 24, wherein the third material comprises PVDC.

[0121] 26. The system according to any one of clauses 17 to 24, wherein the third material comprises EVOH.

[0122] 27. The system according to any one of clauses 1 to 26, wherein the tube is configured to deliver the fluid in a high vacuum system or an ultra-high vacuum system.

[0123] 28. The system according to any one of clauses 1 to 27, wherein the first tubular layer comprises a plurality of first tubular layers.

[0124] 29. The system according to any one of clauses 1 to 28, wherein the second tubular layer comprises a plurality of second tubular layers.

[0125] 30. The system according to any one of clauses 17 to 29, wherein the third tubular layer comprises a plurality of third tubular layers.

[0126] 31. The system according to any one of clauses 1 to 30, wherein the fluid comprises at least one of water or ethylene glycol.

[0127] 32. The system according to any one of clauses 1 to 31, wherein the gas comprises at least one of oxygen or nitrogen.

[0128] 33. The system according to any one of clauses 1 to 32, wherein the system further comprises:

[0129] Fluid bath;

[0130] Multiple rigid tubes are disposed outside the cavity for transferring the fluid between the fluid bath and multiple polyurethane tubes outside the cavity; and

[0131] The tube disposed within the cavity is configured to transfer the fluid between the plurality of polyurethane tubes and the stage.

[0132] 34. The system according to any one of clauses 1 to 33, wherein:

[0133] The stage is configured to move within the cavity; and

[0134] The tube is configured to move together with the platform.

[0135] 35. The system according to any one of clauses 1 to 34, wherein the system includes a scanning electron microscope system.

[0136] 36. The system according to any one of clauses 1 to 35, wherein the system includes a photolithography system.

[0137] 37. The system according to any one of clauses 1 to 36, wherein the tube comprises a plurality of tubes.

[0138] 38. A tube configured to be disposed within a vacuum chamber for conveying fluid between a stage and the outside of the vacuum chamber, the tube comprising:

[0139] A first tubular layer of a first material, wherein the first material is a flexible polymer; and

[0140] A second tubular layer of a second material, wherein the second material is configured to reduce the permeation of fluid or gas through the tube.

[0141] 39. The tube according to Clause 38, wherein the flexible polymer comprises polytetrafluoroethylene (PTFE).

[0142] 40. The tube according to Clause 38, wherein the flexible polymer comprises polyethylene terephthalate (PET).

[0143] 41. The tube according to any one of clauses 38 to 40, wherein the second tubular layer coats the first tubular layer.

[0144] 42. The tube according to any one of clauses 38 to 41, wherein the second material is diamond-like carbon.

[0145] 43. The tube according to any one of clauses 38 to 41, wherein the second material is a metal oxide.

[0146] 44. The tube according to Clause 42, wherein the metal oxide is aluminum oxide.

[0147] 45. The tube according to any one of clauses 38 to 41, wherein the second material is a metal.

[0148] 46. ​​The tube according to Clause 45, wherein the metal is aluminum.

[0149] 47. The tube according to Clause 45, wherein the metal is chromium.

[0150] 48. The tube according to any one of clauses 38 to 41, wherein the second material is a half-metal oxide.

[0151] 49. The tube according to Clause 47, wherein the semi-metal oxide is silicon oxide.

[0152] 50. The tube according to any one of clauses 38 to 41, wherein the second material is a polymer.

[0153] 51. The tube according to Clause 50, wherein the polymer is polyimide.

[0154] 52. The tube according to Clause 50, wherein the polymer is at least one of polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), or ethylene-vinyl alcohol copolymer (EVOH).

[0155] 53. The tube according to any one of clauses 42 to 49, wherein the thickness of the second tubular layer is 10 to 50 nanometers.

[0156] 54. The tube according to any one of clauses 38, 39 or 41 to 53, wherein the tube further comprises a third tubular layer of a third material, wherein the third material is configured to reduce gas permeation through the tube.

[0157] 55. The tube according to clause 54, wherein the third tubular layer is located above the second tubular layer.

[0158] 56. The tube according to Clause 54, wherein the first tubular layer is located above the third tubular layer.

[0159] 57. The tube according to any one of clauses 38, 39 or 41 to 56, wherein the first tubular layer comprises a fluid contact angle greater than 90 degrees.

[0160] 58. The tube according to any one of clauses 38, 39 or 41 to 57, wherein the third tubular layer comprises a fluid contact angle of less than 90 degrees.

[0161] 59. The tube according to any one of clauses 38, 39 or 41 to 58, wherein the tube further comprises an adhesive layer.

[0162] 60. The tube according to any one of clauses 38 to 59 further includes an adhesive layer located between each of the first tubular layer, the second tubular layer, or the third tubular layer.

[0163] 61. The tube according to any one of clauses 59 or 60, wherein the adhesive layer comprises polyimide.

[0164] 62. The pipe according to any one of clauses 54 to 61, wherein the third material comprises PVDC.

[0165] 63. The tube according to any one of clauses 54 to 61, wherein the third material comprises EVOH.

[0166] 64. The tube according to any one of clauses 38 to 63, wherein the tube is configured to deliver the fluid in a high vacuum system or an ultra-high vacuum system.

[0167] 65. The tube according to any one of clauses 38 to 64, wherein the first tubular layer comprises a plurality of first tubular layers.

[0168] 66. The tube according to any one of clauses 38 to 65, wherein the second tubular layer comprises a plurality of second tubular layers.

[0169] 67. The tube according to any one of clauses 54 to 66, wherein the third tubular layer comprises a plurality of third tubular layers.

[0170] 68. The tube according to any one of clauses 38 to 67, wherein the fluid comprises at least one of water or ethylene glycol.

[0171] 69. The tube according to any one of clauses 38 to 68, wherein the gas comprises at least one of oxygen or nitrogen.

[0172] 70. A method for forming a tube, the tube being used within a vacuum chamber to transfer fluid between a stage and the outside of the vacuum chamber, the method comprising:

[0173] A first tubular layer of a first material is formed, wherein the first material is a flexible polymer;

[0174] A second tubular layer of a second material is formed, wherein the second material is configured to reduce the permeation of fluid or gas through the tube; and

[0175] During plasma deposition of the second tubular layer, a negative bias voltage is applied to the tube via a conductive structure.

[0176] 71. The method according to Clause 70, wherein the first tubular layer comprises polytetrafluoroethylene (PTFE).

[0177] 72. The method according to Clause 70, wherein the first tubular layer comprises polyethylene terephthalate (PET).

[0178] 73. The method according to any one of clauses 70 to 72, wherein forming the second tubular layer includes coating the first tubular layer.

[0179] 74. The method according to any one of clauses 70 to 73, wherein the second material is diamond-like carbon.

[0180] 75. The method according to any one of clauses 70 to 73, wherein the second material is a metal oxide.

[0181] 76. The method according to Clause 74, wherein the metal oxide is aluminum oxide.

[0182] 77. The method according to any one of clauses 70 to 73, wherein the second material is a metal.

[0183] 78. The method according to Clause 77, wherein the metal is aluminum.

[0184] 79. The method according to Clause 77, wherein the metal is chromium.

[0185] 80. The method according to any one of clauses 70 to 73, wherein the second material is a half-metal oxide.

[0186] 81. The method according to Clause 80, wherein the semi-metal oxide is silicon oxide.

[0187] 82. The method according to any one of clauses 70 to 73, wherein the second material is a polymer.

[0188] 83. The method according to clause 82, wherein the polymer is a polyimide.

[0189] 84. The method according to clause 82, wherein the polymer is at least one of polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), or ethylene-vinyl alcohol copolymer (EVOH).

[0190] 85. The method according to any one of clauses 70 to 84, wherein the thickness of the second tubular layer is 10 to 50 nanometers.

[0191] 86. The method according to any one of clauses 70, 71 or 73 to 85, further comprising forming a third tubular layer of a third material in the tube, wherein the third material is configured to reduce gas permeation through the tube.

[0192] 87. The method according to Clause 86, wherein the third tubular layer is located above the second tubular layer.

[0193] 88. The method according to Clause 86, wherein the first tubular layer is located above the third tubular layer.

[0194] 89. The method according to any one of clauses 70, 71 or 73 to 88, wherein the first tubular layer comprises a fluid contact angle greater than 90 degrees.

[0195] 90. The method according to any one of clauses 70, 71 or 73 to 89, wherein the third tubular layer comprises a fluid contact angle of less than 90 degrees.

[0196] 91. The method according to any one of clauses 70 to 90 further comprises forming an adhesive layer in the tube.

[0197] 92. The method according to any one of clauses 70 to 91 further comprises forming an adhesive layer between each of the first tubular layer, the second tubular layer, or the third tubular layer.

[0198] 93. The method according to any one of clauses 91 or 92, wherein the adhesive layer comprises polyimide.

[0199] 94. The method according to any one of clauses 86 to 93, wherein the third material comprises PVDC.

[0200] 95. The method according to any one of clauses 86 to 93, wherein the third material comprises EVOH.

[0201] 96. The method according to any one of clauses 70 to 95, wherein the tube is configured to deliver the fluid in a high vacuum system or an ultra-high vacuum system.

[0202] 97. The method according to any one of clauses 70 to 96, wherein forming the first tubular layer includes forming a plurality of first tubular layers.

[0203] 98. The method according to any one of clauses 70 to 97, wherein forming the second tubular layer includes forming a plurality of second tubular layers.

[0204] 99. The method according to any one of clauses 70 to 98, wherein forming the third tubular layer includes forming a plurality of third tubular layers.

[0205] 100. The method according to any one of clauses 70 to 99, wherein the fluid comprises at least one of water or ethylene glycol.

[0206] 101. The method according to any one of clauses 70 to 100, wherein the gas comprises at least one of oxygen or nitrogen.

[0207] 102. The system according to any one of clauses 1 to 37, wherein the tube is a first tube.

[0208] 103. The system described in Clauses 102 further includes a degassing system, comprising:

[0209] A housing, the housing including a plurality of second tubes, wherein the housing is configured to contain the fluid, and

[0210] A vacuum system configured to remove gas from the fluid before the fluid enters the first tube.

[0211] 104. The system according to Clause 103, wherein the vacuum system includes a vacuum pump.

[0212] 105. The system according to Clause 104, wherein the vacuum pump is an air-driven vacuum pump.

[0213] 106. The system according to any one of clauses 102 to 105, wherein the removed gas flows from inside the plurality of second tubes to the vacuum system.

[0214] 107. The system according to any one of clauses 102 to 106, wherein the fluid flows out of the plurality of second pipes.

[0215] 108. The system according to any one of clauses 102 to 107, wherein the plurality of second tubes comprise hollow fiber membranes.

[0216] 109. The system according to Clause 108, wherein the hollow fiber membrane comprises polypropylene.

[0217] 110. The system according to any one of clauses 102 to 109, wherein the first tube comprises a first tubular layer of a first material, wherein the first material is a flexible polymer.

[0218] 111. A system comprising:

[0219] The platform is configured as a fixed chip;

[0220] A cavity is configured to house the stage, and wherein the cavity is configured to operate in a vacuum environment;

[0221] A first tube, disposed within the cavity and configured to transfer fluid between the stage and the outside of the cavity; and

[0222] Degassing system, including:

[0223] A housing, the housing including a plurality of second tubes, wherein the housing is configured to contain the fluid, and

[0224] A vacuum system configured to remove gas from the fluid before the fluid enters the first tube.

[0225] 112. The system according to Clause 111, wherein the vacuum system includes a vacuum pump.

[0226] 113. The system according to Clause 112, wherein the vacuum pump is an air-driven vacuum pump.

[0227] 114. The system according to any one of clauses 111 to 113, wherein the removed gas flows from inside the plurality of second tubes to the vacuum system.

[0228] 115. The system according to any one of clauses 111 to 114, wherein the fluid flows out of the plurality of second pipes.

[0229] 116. The system according to any one of clauses 111 to 115, wherein the plurality of second tubes comprise hollow fiber membranes.

[0230] 117. The system according to Clause 116, wherein the hollow fiber membrane comprises polypropylene.

[0231] 118. The system according to any one of clauses 111 to 117, wherein the first tube comprises a first tubular layer of a first material, wherein the first material is a flexible polymer.

[0232] 119. The system according to Clause 118, wherein the first tube further comprises a second tubular layer of a second material, wherein the second material is configured to reduce the permeation of fluid or gas through the first tube.

[0233] 120. The system according to any one of clauses 1 to 37 or 102 to 110, wherein the system includes an extreme ultraviolet inspection system.

[0234] 121. The system according to any one of clauses 1 to 37 or 102 to 110, wherein the system includes a deep ultraviolet inspection system.

[0235] 122. The system according to any one of clauses 1 to 37 or 102 to 110, wherein the system includes X-rays.

[0236] It should be understood that the embodiments of this disclosure are not limited to the exact constructions described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from the scope of this disclosure.

Claims

1. A system for conveying fluid, comprising: The platform is configured as a fixed chip; A cavity, configured to house the stage, and wherein the cavity is configured to operate in a vacuum environment; and A tube disposed within the cavity and configured to convey fluid between the cavity and its exterior, wherein the tube comprises: A first tubular layer of a first material, wherein the first material is a flexible polymer; and A second tubular layer of a second material, situated above the first tubular layer, wherein the second material is configured to reduce the permeation of fluid or gas through the tubing; and A degassing system is configured to remove air molecules from the conveyed fluid before it enters the tube.

2. The system of claim 1, wherein, The flexible polymer includes polytetrafluoroethylene (PTFE).

3. The system of claim 1, wherein, The flexible polymer includes polyethylene terephthalate (PET).

4. The system of claim 1, wherein, The second tubular layer coats the first tubular layer.

5. The system of claim 1, wherein, The second material is diamond-like carbon.

6. The system of claim 1, wherein, The second material is a metal oxide.

7. The system of claim 6, wherein, The metal oxide is aluminum oxide.

8. The system of claim 1, wherein, The second material is a metal.

9. The system of claim 8, wherein, The metal is aluminum.

10. The system according to claim 8, wherein, The metal in question is chromium.

11. The system according to claim 1, wherein, The second material is a semi-metal oxide.

12. The system according to claim 11, wherein, The semi-metal oxide is silicon oxide.

13. The system according to claim 1, wherein, The second material is a polymer.

14. The system according to claim 13, wherein, The polymer is polyimide.

15. The system according to claim 13, wherein, The polymer is at least one of polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), or ethylene-vinyl alcohol copolymer (EVOH).

16. The system according to claim 5, wherein, The thickness of the second tubular layer is 10-50 nanometers.

17. The system according to claim 1, wherein, The tube also includes a third tubular layer of a third material, wherein the third material is configured to reduce gas permeation through the tube.

18. The system according to claim 17, wherein, The third tubular layer is above the second tubular layer.

19. The system according to claim 17, wherein, The first tubular layer is above the third tubular layer.

20. A method for providing a system for use with a vacuum chamber to transfer fluid between a stage and the outside of the vacuum chamber, the method comprising: Forming a tube, including: A first tubular layer of a first material is formed, wherein the first material is a flexible polymer; A second tubular layer of a second material is formed on top of the first tubular layer, wherein the second material is configured to reduce the permeation of fluid or gas through the tubing; and During plasma deposition of the second tubular layer, a negative bias is applied to the tube via a conductive structure; and A degassing system is provided, the degassing system being configured to remove air molecules from the fluid before the fluid enters the pipe.

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