Method, apparatus, and system for dynamic control of electrostatic chuck during wafer inspection

Abstract

An electrostatic chuck control system is configured for utilization during an inspection process of a wafer, the electrostatic chuck control system including an electrostatic chuck of a stage configured to be undocked during the inspection process, wherein the electrostatic chuck includes a plurality of components configured to affect an interaction between the wafer and the electrostatic chuck during the inspection process, a first sensor configured to generate measurement data between at least some of the plurality of components and the wafer, and a controller including circuitry configured to receive the measurement data to determine a characteristic of the wafer relative to the electrostatic chuck and generate adjustment data to enable adjustment of at least some of the plurality of components based on the determined characteristic while the stage is undocked.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Application 62 / 992,718, filed March 20, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The description in this article relates to the field of charged particle beam devices, and more specifically to a dynamically controlled electrostatic chuck. Background Technology

[0004] Charged particle beam devices can generate two-dimensional images of wafer substrates by detecting secondary electrons, backscattered electrons, mirror electrons, or other types of electrons from the surface of the wafer substrate when struck by a charged particle beam generated by the device. In the semiconductor industry, various charged particle beam devices are used on semiconductor wafers for a variety of purposes, such as wafer processing (e.g., electron beam direct-write lithography systems), process monitoring (e.g., critical-size scanning electron microscopy (CD-SEM)), wafer inspection (e.g., electron beam inspection systems), defect analysis (e.g., defect inspection SEM (e.g., DR-SEM) and focused ion beam systems (or FIB)). During wafer inspection, the wafer is placed on an electrostatic chuck. Placing the wafer on the electrostatic chuck generates an attraction between the wafer and multiple electrodes implemented in the chuck. This attraction between the chuck and the wafer can be achieved by applying a high voltage to the multiple electrodes to attract and stabilize the charged wafer. Furthermore, the chuck can ground the wafer using pins implemented in the chuck, which can bias the wafer to a predetermined voltage level. However, the ability of an electrostatic chuck to perform the above functions may be limited by the position of the electrostatic chuck. Summary of the Invention

[0005] Various embodiments of the present invention provide a multi-beam inspection apparatus, and more specifically, a single-beam inspection system or a multi-beam inspection system, including an improved electrostatic chuck control system. In some embodiments, the inspection system includes: an electrostatic chuck including a plurality of electrodes configured to influence the interaction between a wafer and the electrostatic chuck; a first sensor configured to perform measurements between the plurality of electrodes and the wafer; a driver configured to capture measurements from the first sensor and apply voltages to the plurality of electrodes; and a controller configured to receive measurements captured by the driver to determine whether the wafer is warped during wafer inspection and to adjust the voltages applied to the plurality of electrodes based on the determination.

[0006] In some embodiments, a method is provided for dynamically adjusting parameters of an electrostatic chuck control system for wafer inspection. The method includes: receiving from a first sensor capacitance measured between a plurality of electrodes in the electrostatic chuck and a wafer to determine wafer bending, wherein the plurality of electrodes are configured to influence the interaction between the wafer and the electrostatic chuck when a high voltage is supplied; and providing a first control signal to the electrostatic chuck control system configured to control the electrostatic chuck based on the determination during wafer inspection to adjust the high voltage supplied to the plurality of electrodes.

[0007] In some embodiments, a non-transitory computer-readable medium is provided, storing instructions that, when executed by a processor, cause a device to perform a method for dynamically adjusting parameters during wafer inspection. The method includes: receiving from a first sensor capacitance measured between a plurality of electrodes in an electrostatic chuck and the wafer to determine wafer bending, wherein the plurality of electrodes are configured to influence the interaction between the wafer and the electrostatic chuck when a high voltage is supplied; and providing a first control signal to an electrostatic chuck control system configured to control the electrostatic chuck during wafer inspection based on the determination to adjust the high voltage supplied to the plurality of electrodes. Attached Figure Description

[0008] Figure 1 This is a schematic diagram illustrating an example electron beam inspection (EBI) system according to an embodiment of the present invention.

[0009] Figure 2 This is a schematic diagram illustrating an example electron beam tool according to an embodiment of the present disclosure. The example electron beam tool may be... Figure 1 This is part of an example electron beam inspection system.

[0010] Figure 3 This is an illustration of an exemplary system according to embodiments of the present disclosure for detecting potential problems associated with the interface between the wafer and the electrostatic chuck and for making adjustments in real time during wafer inspection.

[0011] Figure 4A The illustration shows an embodiment according to the present disclosure. Figure 3 A schematic diagram of an embodiment of an exemplary system.

[0012] Figure 4B The illustration shows an embodiment according to the present disclosure. Figure 3 A schematic diagram of another embodiment of the exemplary system.

[0013] Figure 5 This is a flowchart illustrating an exemplary method for dynamically adjusting the parameters of an electrostatic chuck control system according to an embodiment of the present disclosure for wafer inspection. Detailed Implementation

[0014] Now, reference will be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings, wherein, unless otherwise stated, the same reference numerals in different drawings denote the same or similar elements. The implementations set forth in the following description of the exemplary embodiments do not represent all implementations consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with aspects of the invention as described in the appended claims. For example, although some embodiments have been described in the context of utilizing electron beams, this disclosure is not limited thereto. Similarly, other types of charged particle beams can be applied. Furthermore, other imaging systems, such as optical imaging, photoelectric detection, X-ray detection, etc., can be used.

[0015] Electronic devices consist of circuits formed on a silicon wafer called a substrate. Many circuits can be formed together on the same silicon wafer and are called integrated circuits or ICs. The size of these circuits has been reduced so significantly that many of them can be mounted on the substrate. For example, the IC chip in a smartphone can be as small as a thumbnail and can include more than 2 billion transistors, each less than 1 / 1000th the size of a human hair.

[0016] Manufacturing these extremely small ICs is a 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, that is, to improve the overall yield of the process.

[0017] One aspect of improving yield is monitoring the chip fabrication process to ensure that a sufficient number of functional integrated circuits are produced. One way to monitor the process is to inspect the chip's circuit structure at various stages of its formation. This can be done using a scanning electron microscope (SEM). SEMs can be used to image these extremely small structures; essentially, they take "photographs" of the wafer's structure. This image can be used to determine if the structure is formed properly and in the correct location. If defects are found in the structure, the process can be adjusted to make it less likely to recur.

[0018] A Sequencing Electron Microscope (SEM) works similarly to a camera. A camera takes an image by receiving and recording the brightness and color of light reflected or emitted from a person or object. A Sequencing Electron Microscope (SEM) takes a “photograph” by receiving and recording the energy or amount of electrons reflected or emitted from a structure. Before taking this “photograph,” an electron beam can be provided to the structure, and as electrons are reflected or emitted from the structure (“emissions”), the SEM’s detector can receive and record the energy or amount of these electrons to generate an image. To take this “photograph,” 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 “photographs” of the wafer. By using multiple electron beams, the SEM can provide more electron beams to the structure to obtain these multiple “images,” resulting in more electrons being emitted from the structure. Therefore, the detector can receive more emitted electrons simultaneously and generate images of the wafer’s structure with greater efficiency and faster speed.

[0019] Typically, structures are fabricated on a substrate (e.g., a silicon substrate), which is placed on a platform called a stage for imaging. This stage holds and moves the wafer and also includes an electrostatic chuck to hold the wafer securely to the stage. Some electrostatic chucks have three main functions: clamping the wafer onto the stage; detecting the wafer by measuring the capacitance between the electrostatic chuck and the wafer; and grounding the wafer to a high voltage.

[0020] To perform these functions, the electrostatic chuck can be connected to a contact tower that provides power to the chuck. In some conventional systems, the chuck is only connected to the contact tower when the stage is in the loading position for loading the wafer. Therefore, when the stage moves from the loading position, the chuck is disconnected from the contact tower, preventing it from having the power required to perform its functions. As a result, SEM may have difficulty detecting and responding to problems caused by the interaction between the chuck and the wafer during inspection.

[0021] To overcome these problems, some conventional systems have a permanent connection between the electrostatic chuck and the power supply. However, due to the large voltage difference between the electrostatic chuck and the wafer, arcing may occur between the electrostatic chuck and the wafer, so this type of connection can damage the electrostatic chuck during the inspection process. For example, arcing may occur when the wafer is connected to a high voltage (e.g., 30kV) and a lower voltage (e.g., 1kV) is supplied to the electrostatic chuck during inspection.

[0022] Some embodiments of this disclosure provide an improved circuit system for controlling the power supplied to an electrostatic chuck during wafer inspection. This circuit system may include an amplifier that can adjust one or more voltages from a high-voltage supply and supply the adjusted voltage to the electrostatic chuck. Because the electrostatic chuck has a high voltage, the voltage difference between the electrostatic chuck and the wafer is low, thereby reducing the risk of arc discharge.

[0023] The circuitry can also be configured to receive signals from a controller. The controller can be configured to check measurements (e.g., clamping voltage, capacitance between the electrostatic chuck and the wafer, grounding resistance between two pins implemented in the electrostatic chuck) and adjust the circuitry by providing signals to it. For example, based on received measurements, if the controller determines that the clamping voltage has dropped below a predetermined threshold, it can report an error or attempt to increase the clamping voltage by providing a signal to the circuitry. As another example, based on received measurements, the controller can determine that wafer bending may be occurring (resulting in a warped wafer) and can adjust certain clamping voltages to minimize bending. Furthermore, based on received measurements indicating that the wafer may not be properly grounded, the controller can signal the circuitry to connect the wafer to a high voltage. By dynamically adjusting the parameters of the circuitry, the SEM can detect potential problems and make adjustments in real time, significantly improving the reliability of the SEM.

[0024] For clarity, the relative dimensions of the components in the accompanying drawings may be enlarged. In the following description of the drawings, the same or similar reference numerals refer to the same or similar components or entities, and only the differences with respect to the various embodiments are described.

[0025] As used herein, unless otherwise expressly stated, the term "or" covers all possible combinations except those that are not feasible. For example, if a statement component can contain A or B, then unless otherwise expressly stated or not feasible, the component can contain A or B or A and B. As a second example, if a statement component can contain A, B, or C, then unless otherwise stated or not feasible, the component can contain A, or B, or C, or A and B, or A and C, or B and C, or A and B and C.

[0026] Figure 1 An exemplary electron beam inspection (EBI) system 100 according to an embodiment of the present disclosure is illustrated. The EBI system 100 can be used for imaging. Figure 1As shown, the EBI system 100 includes a main chamber 101, a loading / locking chamber 102, an electron beam tool 104, and a device front-end module (EFEM) 106. The electron beam tool 104 is located within the main chamber 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 a wafer front-opening transfer cassette (FOUP), which contains wafers to be inspected (e.g., semiconductor wafers or wafers made of one or more other materials) or samples to be inspected (wafers and samples can be used interchangeably). A “lot” is a plurality of wafers that can be loaded for batch processing.

[0027] 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.

[0028] Controller 109 is electrically connected to electronic 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 outside the structure that includes the main chamber 101, the load / lock chamber 102 and the EFEM 106, but it should be understood that the controller 109 may be part of the structure.

[0029] 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 combination of any number of the following: a central processing unit (or “CPU”), a graphics processing unit (or “GPU”), an optical processor, a programmable logic controller, a microcontroller, a microprocessor, a digital signal processor, an intellectual property (IP) core, a programmable logic array (PLA), a programmable array logic (PAL), a general-purpose array logic (GAL), a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a system-on-a-chip (SoC), an application-specific integrated circuit (ASIC), and any type of circuit capable of performing data processing. A processor may also be a virtual processor, comprising one or more processors distributed across multiple machines or devices connected via a network.

[0030] In some embodiments, controller 109 may also include one or more memories (not shown). The memory may 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, the memory may include any combination of any number of the following: 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 type of storage device. The code may include an operating system (OS) and one or more applications (or “apps”) for a specific task. The memory may also be virtual memory, comprising one or more memories distributed across multiple machines or devices connected via a network.

[0031] Figure 2 An example imaging system 200 according to an embodiment of the present disclosure is illustrated. Figure 2 The electron beam tool 104 can be configured for use with the EBI system 100. The electron beam tool 104 can be a single-beam device or a multi-beam device. For example... Figure 2As shown, the electron beam tool 104 includes a motorized sample stage 201 and a wafer holder 202 supported by the motorized sample stage 201 to hold the wafer 203 to be inspected. The electron beam tool 104 also includes an objective lens assembly 204, an electron detector 206 (which includes electron sensor surfaces 206a and 206b), an objective aperture 208, a converging lens 210, a beam-limiting aperture 212, a gun aperture 214, an anode 216, and a cathode 218. In some embodiments, the objective lens assembly 204 may include a modified oscillating deceleration immersion objective (SORIL) including an electrode 204a, a control electrode 204b, a deflector 204c, and an excitation coil 204d. Additionally, the electron beam tool 104 may include an energy dispersive X-ray spectrometer (EDS) detector (not shown) for characterizing materials on the wafer 203.

[0032] A primary electron beam 220 is emitted from the cathode 218 by applying an accelerating voltage between the anode 216 and the cathode 218. The primary electron beam 220 passes through both the gun aperture 214 and the beam-limiting aperture 212, both of which determine the size of the electron beam entering the converging lens 210, located below the beam-limiting aperture 212. The converging lens 210 focuses the primary electron beam 220 before it enters the objective aperture 208, thus setting the size of the electron beam before it enters the objective assembly 204. A deflector 204c deflects the primary electron beam 220 to facilitate beam scanning on the wafer. For example, during scanning, the deflector 204c can be controlled to sequentially deflect the primary electron beam 220 to different positions on the top surface of the wafer 203 at different time points to provide data for image reconstruction of different portions of the wafer 203. Furthermore, the deflector 204c can be controlled to deflect the primary electron beam 220 onto different sides of the wafer 203 at a specific location at different time points to provide data for stereoscopic image reconstruction of the wafer structure at that location. Further, in some embodiments, the anode 216 and cathode 218 can generate multiple primary electron beams 220, and the electron beam tool 104 can include multiple deflectors 204c to simultaneously project multiple primary electron beams 220 onto different portions / sides of the wafer to provide data for image reconstruction of different portions of the wafer 203.

[0033] Excitation coil 204d and electrode 204a generate a magnetic field that begins at one end of electrode 204a and terminates at the other end. A portion of wafer 203 scanned by primary electron beam 220 can be immersed in the magnetic field and become charged, which in turn generates an electric field. The electric field reduces the impact energy of the primary electron beam 220 near the surface of wafer 203 before it collides with the wafer 203. Control electrode 204b, electrically isolated from electrode 204a, controls the electric field on wafer 203 to prevent micro-arc discharge on wafer 203 and ensure proper beam focusing.

[0034] Upon receiving the primary electron beam 220, a secondary electron beam 222 can be emitted from a portion of the wafer 203. The secondary electron beam 222 can form a beam spot on the sensor surfaces 206a and 206b of the electron detector 206. The electron detector 206 can generate a signal representing the beam spot intensity (e.g., voltage, current, etc.) and provide this signal to the image processing system 250. The intensity of the secondary electron beam 222 and the resulting beam spot can vary depending on the external or internal structure of the wafer 203. Moreover, as discussed above, the primary electron beam 220 can be projected onto different locations on the top surface of the wafer or onto different sides of the wafer at specific locations to generate secondary electron beams 222 (and resulting beam spots) of varying intensities. Therefore, by mapping the intensity of the beam spot to the position of the wafer 203, the processing system can reconstruct an image reflecting the internal or surface structure of the wafer 203.

[0035] As discussed above, imaging system 200 can be used to inspect wafer 203 on motorized sample stage 201 and includes electron beam tool 104. Imaging system 200 may also include image processing system 250, which includes image acquisition unit 260, storage device 270, and controller 109. Image acquisition unit 260 may include one or more processors. For example, image acquisition unit 260 may include a computer, server, mainframe, terminal, personal computer, any type of mobile computing device, or a combination thereof. Image acquisition unit 260 can be connected to detector 206 of electron beam tool 104 via a medium such as an electrical conductor, optical fiber, portable storage medium, IR, Bluetooth, Internet, wireless network, radio, or a combination thereof. Image acquisition unit 260 can receive signals from detector 206 and can construct an image. Therefore, image acquisition unit 260 can acquire an image of wafer 203. Image acquisition unit 260 can also perform various post-processing functions, such as generating contours, overlaying indicators on the acquired image, etc. Image acquisition unit 260 can perform adjustments such as brightness and contrast on the acquired image. Storage device 270 can be a storage medium such as a hard disk, cloud storage device, random access memory (RAM), or other types of computer-readable storage. Storage device 270 can be coupled to image acquisition unit 260 and can be used to save scanned raw image data as raw images and post-processed images. Image acquisition unit 260 and storage device 270 can be connected to controller 109. In some embodiments, image acquisition unit 260, storage device 270, and controller 109 can be integrated into a single control unit.

[0036] In some embodiments, image acquirer 260 may acquire one or more images of a sample based on imaging signals received from detector 206. The imaging signals may correspond to a scanning operation for imaging charged particles. The acquired image may be a single image comprising multiple imaging regions. The single image may be stored in storage device 270. The single image may be a raw image that can be divided into multiple partitions. Each partition may include an imaging region containing features of wafer 203.

[0037] The interaction between the wafer holder 202 and the wafer 203 can cause several problems. For example, charge may accumulate between the wafer 203 and the wafer holder 202, making it more difficult to remove the wafer 203 from the wafer holder 202 and delaying the yield. As another example, a warped wafer 203 may cause problems not only in generating accurate images but also in retrieving the wafer 203 from the wafer holder 202, thus slowing down the yield of the EBI system. Figure 3The system described herein can detect such problems and make adjustments in real time during the inspection of wafer 203.

[0038] Figure 3 This is an illustration of an exemplary system 300 for controlling an electrostatic chuck operating at high voltage during an inspection process, according to embodiments of the present disclosure. System 300 may include an electrostatic chuck control system 302, an electrostatic chuck 306 for holding a wafer 304, and a controller 322.

[0039] In some embodiments, chip 304 may be Figure 2 The chip 203 in the middle, while the electrostatic chuck 306 can be Figure 2 The wafer holder 202 is included. The wafer 304 may include a back-side film. The back-side film may include a thin layer of dielectric or other protective material, such as silicon dioxide or nitride.

[0040] To perform wafer clamping, wafer inspection, and wafer grounding functions, the electrostatic chuck control system 302 may include an electrostatic chuck driver 330, which generates one or more signals to adjust one or more high voltages supplied to electrodes 310A to 310B and 311A ​​to 311B. When energized, electrodes 310A to 310B and 311A ​​to 311B can attract and hold the wafer 304 to the electrostatic chuck 306 via an electrostatic field. The electrostatic field allows capacitive coupling between the electrostatic chuck 306 and the wafer 304 to electrically connect them. For example, a positively charged electrostatic chuck 306 may attract a negatively charged wafer 304, and a negatively charged electrostatic chuck 306 may attract a positively charged wafer 304. A high-voltage supply can supply one or more voltages to the electrostatic chuck control system 302, wherein the electrostatic chuck driver 330 can adjust one or more of the supplied voltages to feed into the plurality of electrodes 310A to 310B and 311A ​​to 311B implemented in the electrostatic chuck 306. For example, the electrostatic chuck driver 330 can function as a high-voltage amplifier that can adjust the voltage supplied by the high-voltage supply upon receiving an adjustment configuration from the controller 322 and deliver one or more adjusted voltages to the electrodes 310A to 310B and 311A ​​to 311B.

[0041] In some embodiments, the regions of electrodes 310A to 310B and 311A ​​to 311B used for contacting wafer 304 may be the same. The voltage polarities of electrodes 310A to 310B and electrodes 311A ​​to 311B may be the same or opposite, wherein when, for example, wafer 304 is grounded, the voltage polarities of electrodes 310A to 310B and electrodes 311A ​​to 311B may be the same. Electrodes 310A to 310B and 311A ​​to 311B can also be used as capacitors to provide information about the capacitance of wafer 306.

[0042] The electrostatic chuck driver 330 can also generate signals to configure the ground pin 313 to the grounded wafer 304 via pins 312A, 312B, or 313, wherein the electrostatic chuck driver 330 is electrically connected to pin 313 (connection not depicted). Pins 312A to 312B and 313 can be electrically connected between the ground pulse generator 360 and the wafer 304. In some embodiments, the ground pin 313 (or high-voltage pin) can be pressed against the back-side film of the wafer 304 without completely penetrating the back-side film to bias the wafer 304 to a predetermined level, and pins 312A to 312B can contact the back-side film.

[0043] like Figure 3 As shown, the electrostatic chuck control system 302 may include a capacitance measurement sensor 340 and a grounding resistance measurement sensor 350. Although Figure 3Sensors 340 and 350 are shown to be located inside the electrostatic chuck control system 302; however, it should be understood that sensors 340 and 350 may be located outside the electrostatic chuck control system 302. The capacitance measurement sensor 340 and the grounding resistance measurement sensor 350 can detect or measure electrical characteristics associated with the interface between the wafer 304 and the electrostatic chuck 306, and provide the measured characteristics to the controller 322. For example, the electrical characteristics may include at least one of the following: impedance, resistance, capacitive reactance, admittance, conductance, or capacitive susceptance. The capacitance measurement sensor 340 can measure the capacitance between the electrostatic chuck 306 and the wafer 304, and provide a measurement signal (indicating the measured characteristic / value, or an indication associated with the measured characteristic / value) to the controller 322, which can determine whether the wafer 304 is properly positioned on the electrostatic chuck 306 based on these measurement signals. Electrodes 310A to 310B and 311A ​​to 311B can be used as capacitors to provide information about the capacitance of the wafer 306. If the measured capacitance between electrodes 310A to 310B and 311A ​​to 311B exceeds a predetermined range, controller 322 can determine that the wafer is not properly positioned on electrostatic chuck 306. For example, the capacitance between electrostatic chuck 306 and wafer 304 can be monitored by monitoring the current flowing between any of these electrodes or pins in response to an A / C voltage applied to one or more of electrodes 310A to 310B or 311A ​​to 311B or pins 312A to 312B or 313. A change in the measured current exceeding a predetermined threshold can indicate that wafer 304 has bent.

[0044] The ground resistance measurement sensor 350 can be electrically connected to pins 312A or 312B. The ground signal transmitted from the ground pulse generator 360 can be, for example, a voltage pulse or set of pulses designed to penetrate the protective coating of wafer 304, which can enter wafer 304 through pin 313 and exit through pins 312A or 312B. The ground resistance measurement sensor 350 can measure the electrical characteristics of a first electrical breakdown and a second electrical breakdown, and provide the measured values ​​to the controller 322, whereby the first electrical breakdown occurs through the back-side film of wafer 304 between pin 313 and wafer 304, and the second electrical breakdown occurs through the back-side film between wafer 304 and pins 312A or 312B. In some embodiments, capacitive coupling can be formed between wafer 304 on the wafer stage and conductors (e.g., electrostatic chuck 306 or electrodes 310A to 310B or 311A ​​to 311B). For example, wafer 304 on the wafer stage and conductors can form a capacitor. Capacitive coupling can be used as an electrical path (“return path”) for the ground signal. The electrical connectivity of capacitive coupling can be checked using an alternating current (AC) signal entering through pin 313. When the AC signal flows and forms a current loop, sensor 350 can transmit a signal indicating the current loop to controller 322, and controller 322 can determine that capacitive coupling has been established. In some embodiments, the quality of the electrical connection between pin 313 and wafer 304 can be verified by measuring the AC signal. In some embodiments, ground resistance measurement sensor 350 can measure the voltage between pin 313 and either pin 312A or 312B, which can be used to assess the ground level. When the resistance between pin 313 and pins 312A or 312B is below a predetermined threshold level, the wafer can be considered adequately grounded. For example, the voltage between electrostatic chuck 306 and wafer 304 can be monitored by monitoring the current flowing between any of these electrodes or pins in response to an A / C voltage applied to one or more of electrodes 310A to 310B or 311A ​​to 311B or pins 312A to 312B or 313. A measured change in current below a predetermined threshold can indicate that chip 304 is adequately grounded.

[0045] In some embodiments, the electrostatic chuck driver 330 can be configured to receive measured values ​​from the capacitance measurement sensor 340 and the ground resistance measurement sensor 350, transmit the received measured values ​​to the controller 322, and receive data (communication) from the controller 322. For example, if the electrostatic chuck control system 302 includes the capacitance measurement sensor 340 and the ground resistance measurement sensor 350, the electrostatic chuck driver 330 can receive measurement signals from the sensors 340 and 350 and provide measurement signals (indicating measured values ​​or indications associated with the measured values) to the controller 322. It should be understood that this is only one example of a configuration, and any number of other configurations are possible.

[0046] The controller 322 can be electrically connected to the electrostatic chuck control system 302 and can control the electrostatic chuck control system 302 to generate signals. In some embodiments, the controller 322 can be implemented as follows: Figures 1 to 2 It is part of controller 109. In some embodiments, controller 322 may be implemented as a controller independent of controller 109, such as a software module or a hardware module.

[0047] The controller 322 can provide instructions (or control parameters) to configure the signal provided by the electrostatic chuck driver 330. The signal may include at least one of the following: voltage, current, voltage or current distribution, frequency of the distribution, period of the distribution, phase of the distribution, amplitude of the distribution, or duration of the voltage or current. The configured signal enables the electrostatic chuck control system 302 to ground the wafer 304 during inspection by adjusting one or more voltages supplied to electrodes 310A to 310B and 311A ​​to 311B using pin 313. The controller 322 may be a real-time controller that can read and make appropriate adjustments to measurements received from sensors 340 and 350 (e.g., clamping voltage, capacitance between the electrostatic chuck 306 and the wafer 304, grounding resistance between the two grounding pins 313 and any one of 312A to 312B). For example, if controller 322 detects that the wafer clamping voltage has dropped below a predetermined threshold based on measurements provided by sensor 340, controller 322 may provide a control signal to electrostatic chuck control system 302 (or electrostatic chuck driver 330) to adjust one or more voltages applied to electrodes 310A to 310B and 311A ​​to 311B to assist clamping. A drop in wafer clamping voltage can cause serious problems during wafer 304 inspection. For example, while a motorized stage (e.g., motorized sample stage 201 including electrostatic chuck 306) is moving, wafer 304 may detach from electrostatic chuck 306, thereby damaging the wafer and adding problematic debris to the inspection environment. In another example, if controller 322 detects a weakening attraction between wafer 302 and electrostatic chuck 306 based on capacitance measurements from sensor 340, controller 322 can provide a control signal to electrostatic chuck control system 302 (or electrostatic chuck driver 330) to apply one or more voltages to electrodes 310A-310B and 311A-311B to increase the clamping voltage. Sensor 340 can detect that some portions of wafer 304 may not be making sufficient contact with the electrostatic chuck 306 where wafer 304 is located.

[0048] The controller 322 can also detect whether the wafer 304 is bent or warped by changes in capacitance values ​​(e.g., via electrodes 310A to 310B and 311A ​​to 311B). For example, the controller 322 can determine that the capacitance measurement via electrodes 310A to 310B is different from the capacitance measurement via electrodes 311A ​​to 311B, which can indicate that the wafer 304 is warped or bent in some way. If the capacitance measurement is determined to indicate that the wafer is bent or warped, the controller 322 may instruct the electrostatic chuck control system 302 via a control signal to adjust one or more voltages applied to electrodes 310A to 310B and 311A ​​to 311B to increase the clamping voltage.

[0049] If the controller 322 detects that the wafer 304 is not properly connected to a high voltage (such as a decrease in ground resistance) based on a ground resistance measurement from the sensor 350, the controller 322 can also provide a signal to ground the wafer 304. The controller 322 can determine to provide a ground signal. Ground determination may include: 1) enabling a ground pulse generator 360, which is configured to provide a series of high-voltage pulses to pins 313, 312A, or 312B, such that dielectric breakdown occurring at the back-side film of the wafer 304 forms a current path through the back-side film and another pin (such as pin 313); 2) measuring the voltage between any of the pins 313, 312A, or 312B by the sensor 350; and 3) comparing the measured voltage with a predetermined voltage by the controller 322. Therefore, the controller 322 can detect problems caused by the interface between the wafer 304 and the electrostatic chuck 306 during inspection and make adjustments to resolve these problems in real time. The controller 322 can also report any errors that occur during inspection to external systems.

[0050] Figure 4A The illustration shows an embodiment according to the present disclosure. Figure 3 A schematic diagram of an embodiment of an exemplary system. Figure 4A The system 400A may include an electrostatic chuck control system 402A, an electrostatic chuck 406A, a controller 422A, and a bus 426A connecting the electrostatic chuck control system 402A and the controller 422A. The functions of the electrostatic chuck control system 402A, the electrostatic chuck 406A, and the controller 422A may be respectively related to… Figure 3 The electrostatic chuck control system 302, electrostatic chuck 306, and controller 322 have similar functions. For example... Figure 4AAs shown, a high-voltage supply can provide voltage to the electrostatic chuck control system 402A and the electrostatic chuck 406A, while the controller 422A may not receive such voltage from the high-voltage supply. In some cases, the bus 426A can be an optical fiber and can be configured to transmit data between the electrostatic chuck control system 402A and the controller 422A. When the controller 422A is at a low voltage and the electrostatic chuck control system 402A is at a high voltage, the optical fiber can be used to isolate the two circuits implemented in the electrostatic chuck control system 402A and the controller 422A. The voltage supplied to the electrostatic chuck control system 402A and the electrostatic chuck 406A may be different from the voltage applied to the wafer (e.g., Figure 3 The voltages on the chip 304 in the electrostatic chuck may be the same or different. The electrostatic chuck control system 402A can adjust one or more voltages supplied to the electrostatic chuck based on communications received from the controller 422A. As explained above, the controller 422A can adjust the voltages based on communications received from sensors (e.g., Figure 3 The measured values ​​received by the sensor 340 or 350 are transmitted to the electrostatic chuck control system 402A via signals, enabling the electrostatic chuck control system 402A to make adjustments, thereby instructing the electrostatic chuck control system 402A (e.g., via...) Figure 3 The driver 330 in the electrostatic chuck increases the clamping voltage. For example, one or more of the provided voltages can be in the range of 0kV to 30kV. Moreover, one or more high voltages provided to the electrostatic chuck 406A can keep the voltage difference between the wafer and the electrostatic chuck 406A low (e.g., 1kV), which can help and in some cases make it possible to avoid wafer bending.

[0051] Figure 4B The illustration shows an embodiment according to the present disclosure. Figure 3 A schematic diagram of another embodiment of the exemplary system. Figure 4B System 400B may include an electrostatic chuck control system 402B, an electrostatic chuck 406B, a controller 422B, and a bus 426B connecting the electrostatic chuck control system 402B and the controller 422B. The functions of the electrostatic chuck control system 402B, the electrostatic chuck 406B, and the controller 422B may respectively correspond to… Figure 4A The electrostatic chuck control system 402A, electrostatic chuck 406A, and controller 422A in the text have similar functions. For example... Figure 4BAs shown, a high-voltage supply can provide one or more voltages to the electrostatic chuck control system 402A, the electrostatic chuck 406A, and the controller 422A. In some embodiments, bus 426A can be an optical fiber and can be configured to transmit data between the electrostatic chuck control system 402A and the controller 422A. In some embodiments, bus 426A can be a communication component other than an optical fiber and can be configured to transmit data between the electrostatic chuck control system 402A and the controller 422A.

[0052] Figure 5 This is a flowchart illustrating an example method 500 for dynamically adjusting parameters of an electrostatic chuck (e-chuck) control system for wafer inspection, according to an embodiment of the present disclosure. Method 500 can be performed by a controller that can be coupled to a charged particle beam device (e.g., EBI system 100). For example, the controller could be... Figure 2 Controller 109 in Figure 3 Controller 322 in Figure 4A Controller 422A or Figure 4B The controller is 422B. The controller can be programmed to implement method 500.

[0053] In step 505, the controller (e.g., Figure 2 The controller 109 in the middle can provide one or more control signals to unlock the motorized sample stage (e.g., during wafer inspection) Figure 2 The motorized sample stage 201 in the image. The motorized sample stage may include an electrostatic chuck for holding the wafer, and the electrostatic chuck may include multiple components configured to influence the interaction between the wafer and the electrostatic chuck during wafer inspection. For example, the control signal may include at least one of the following: voltage, current, voltage or current distribution, frequency of the distribution, period of the distribution, phase of the distribution, amplitude of the distribution, or duration of the voltage or current, and the control signal may unlock the motorized sample stage to transport the wafer into the main chamber (e.g., ...). Figure 1 The main chamber 101 in the middle), so as to be transmitted through an electron beam tool (e.g., Figure 1 The electron beam tool 104 in the process handles the wafer inspection procedure. For example, the motorized sample stage can be configured to move to predetermined coordinates to use the electron beam (e.g., Figure 2 The electron beam 220 in the process inspects the wafer. The wafer inspection process may include: after placing the wafer at predetermined coordinates, scanning the wafer with an electron beam to inspect the wafer. In some prior art systems, unlocking the stage disconnects the stage from the high-voltage power supply. Advantageously, for the currently disclosed embodiments, unlocking the stage does not disconnect the stage from the high-voltage power supply.

[0054] In step 510, the controller can obtain information from the first sensor (e.g., Figure 3 The sensor 340 in the middle receives first data indicating capacitance, which is located between one or more of a plurality of electrodes implemented in an electrostatic chuck (e.g., E-chuck) and the wafer. The first data can be analyzed to determine wafer bending. For example, the controller can: based on the capacitance measurement from the sensor (e.g., Figure 3 The sensor 340 in the controller receives a capacitance measurement and determines that the wafer tends to be released from the electrostatic chuck by comparing the received capacitance measurement with a predetermined capacitance measurement. As another example, the controller may determine that the wafer tends to be released from the electrostatic chuck based on received data indicating the current flowing through one or more pins or electrodes (e.g., electrodes 310A to 310B, 311A ​​to 311B, pins 312A to 312B, 313), and may determine that the wafer tends to be released from the electrostatic chuck based on the received data.

[0055] In step 520, the controller may send a signal to the electrostatic chuck control system (e.g., Figure 3 The electrostatic chuck control system 302 provides a control signal that enables the electrostatic chuck control system to adjust the voltage applied to the electrodes implemented in the electrostatic chuck based on first data, which may indicate wafer bending. For example, the control signal may include at least one of the following: voltage, current, voltage or current distribution, frequency of distribution, period of distribution, phase of distribution, amplitude of distribution, or duration of voltage or current, and the control signal may enable the electrostatic chuck control system to adjust one or more voltages applied to the electrodes. One or more adjusted voltages may attract and hold the wafer in place on the chuck, and remove wafer bending (e.g., by compensating for wafer bending via electrodes 310 and 311). For example, a positively charged electrode in the electrostatic chuck may attract a negatively charged wafer, and a negatively charged electrode in the electrostatic chuck may attract a positively charged wafer.

[0056] In step 530, the controller can receive a measured resistance from the second sensor regarding the connection between the wafer and the electrostatic chuck to determine whether the connection to the wafer has a sufficiently low resistance that would allow the wafer to be grounded adequately. For example, a grounding resistance measuring sensor (e.g., Figure 3 The sensor 350 in the middle can measure two pins (e.g., Figure 3 The voltage between pins 312A and 312B, 313 and 312A, 313 and 312B, etc., is measured and transmitted to the controller. After receiving the measured voltage, the controller can compare the received voltage with a predetermined voltage to determine whether the resistance needs to be reduced, which may enable improvements to the chip's grounding.

[0057] In step 540, the controller may provide one or more control signals to the electrostatic chuck control system to enable the electrostatic chuck control system to bias the wafer to a predetermined voltage level. For example, the one or more control signals may include at least one of the following: voltage, current, voltage or current distribution, frequency of the distribution, period of the distribution, phase of the distribution, amplitude of the distribution, or duration of the voltage or current, and the control signals may enable the electrostatic chuck control system to configure sharp pins (e.g., Figure 3 Pin 313 in the image is used to penetrate the protective coating of the wafer and bias the wafer to a predetermined voltage level. When the electron beam interacts with the wafer, it can charge the wafer and render it no longer electrically neutral. The charged wafer can acquire a voltage and affect the departing electrons, which can affect image quality. Therefore, ensuring proper grounding of the wafer may be advantageous to improve imaging.

[0058] In step 550, the controller (e.g., Figure 2 The controller 109 in the controller can provide one or more control signals to dock with the motorized sample stage. For example, the one or more control signals may include at least one of the following: voltage, current, voltage or current distribution, frequency of the distribution, period of the distribution, phase of the distribution, amplitude of the distribution, or duration of the voltage or current, and the control signal can dock with the motorized sample stage after the wafer inspection process to transfer the wafer to the loading chamber / locking chamber (e.g., Figure 1 (Loading chamber / locking chamber 102 in the middle).

[0059] The various aspects of this disclosure are set forth in the following numbered clauses:

[0060] 1. An electrostatic chuck control system configured for use during a wafer inspection process, the electrostatic chuck control system comprising:

[0061] An electrostatic chuck for a stage, the stage being configured to be disengaged during the inspection process, wherein the electrostatic chuck includes multiple components configured to influence the interaction between the wafer and the electrostatic chuck during the inspection process;

[0062] A first sensor is configured to generate measurement data between at least some of a plurality of components and the wafer; and

[0063] The controller includes a circuit system configured to receive measurement data to determine the characteristics of the wafer relative to an electrostatic chuck and generate adjustment data to enable adjustment of at least some of a plurality of components based on the determined characteristics while the stage is being disengaged.

[0064] 2. The electrostatic chuck control system according to Clause 1 further includes a driver that is communicatively coupled to the controller and configured to apply control signals to a plurality of components to enable adjustment of the plurality of components.

[0065] 3. The electrostatic chuck control system according to Clause 1 or 2, wherein the stage is configured to move to a predetermined position during the inspection process after the stage is disengaged.

[0066] 4. The electrostatic chuck control system according to Clause 3, wherein the stage is configured to move to a predetermined position during the inspection process so that the charged particle system can scan the wafer.

[0067] 5. The electrostatic chuck control system according to any one of Clauses 2 to 4 further includes a power supply that provides power to the driver and controller.

[0068] 6. The electrostatic chuck control system according to any one of Clauses 2 to 5 further includes an optical fiber connecting the driver and the controller and configured to transmit data between the driver and the controller.

[0069] 7. The electrostatic chuck control system according to any one of Clauses 1 to 6, wherein the controller includes a real-time controller.

[0070] 8. The electrostatic chuck control system according to any one of Clauses 1 to 7, wherein the plurality of components include a plurality of electrodes configured to influence the interaction between the wafer and the electrostatic chuck by generating an electric field.

[0071] 9. The electrostatic chuck control system according to Clause 8, wherein the measurement data generated by the first sensor includes capacitance measurement data between multiple electrodes and the wafer.

[0072] 10. The electrostatic chuck control system according to Clause 8 or 9, wherein the plurality of electrodes includes a first electrode set and a second electrode set, wherein the first electrode set and the second electrode set are configured to provide data to determine whether the wafer is bent during the inspection process.

[0073] 11. The electrostatic chuck control system according to any one of Clauses 1 to 10, wherein the plurality of components include a plurality of pins configured to influence the interaction between the wafer and the electrostatic chuck by transmitting pulses to the wafer.

[0074] 12. The electrostatic chuck control system according to Clause 11 further includes:

[0075] The second sensor is configured to generate resistance measurement data corresponding to the resistance of the connections between multiple pins and the chip. The controller is also configured to receive the resistance measurement data to determine whether to generate adjustment data for adjusting the resistance of the connections.

[0076] 13. The electrostatic chuck control system according to Clause 11 or 12 further includes a ground pulse generator configured to generate a pulse to the wafer and receive adjustment data from the controller, such that at least some of the pins among the plurality of pins can be adjusted based on the determination.

[0077] The pulse is a high-voltage pulse.

[0078] 14. The electrostatic chuck control system according to any one of Clauses 1 to 13, wherein the controller is further configured to report errors to an external system based on received measurements.

[0079] 15. A method for dynamically adjusting parameters of an electrostatic chuck control system during a wafer inspection process, the method comprising:

[0080] After the stage, including the electrostatic chuck, is detached for inspection, measurement data is received, which is generated based on the interaction between the wafer and multiple components implemented in the electrostatic chuck.

[0081] Based on measurement data, the characteristics of the wafer relative to the electrostatic chuck were determined; and

[0082] Based on the determination, a transmission signal is made so that at least some of the multiple components can be adjusted while the stage is being disengaged.

[0083] 16. The method described under Clause 15 further includes:

[0084] Receive resistance measurement data to determine whether to generate adjustment data for adjusting the resistance of the connection; wherein the resistance measurement data is generated by a second sensor configured to generate resistance measurement data corresponding to the resistance of the connection between multiple components and the wafer; and

[0085] Based on the determination, at least some of the components among the multiple components are enabled.

[0086] 17. A non-transitory computer-readable medium storing a set of instructions executable by a controller of a device to cause the device to perform a method for dynamically adjusting parameters of an electrostatic chuck control system while a stage coupled to an electrostatic chuck is disengaged, the method comprising:

[0087] While the stage is detached for wafer inspection, measurement data is received to determine the characteristics of the wafer relative to the electrostatic chuck, wherein the measurement data is generated based on the interactions between the wafer and multiple first components implemented in the electrostatic chuck; and

[0088] While the stage is being disconnected, at least some of the first components among a plurality of first components are adjusted based on the determined characteristics.

[0089] 18. The non-transitory computer-readable medium as described in Clause 17, wherein the instruction set is executable by the controller of the device to cause the device to also perform:

[0090] Receive resistance measurement data to determine whether to generate adjustment data for adjusting the resistance between the plurality of second components and the wafer, wherein the resistance measurement data is generated based on the interaction between the plurality of second components and the wafer; and

[0091] Based on the determination of whether adjustment data is generated, at least some of the multiple second components are adjusted.

[0092] 19. A method comprising:

[0093] The stage, including the electrostatic chuck, is disengaged to enable the wafer inspection process.

[0094] Measurement data is generated based on the interaction between the wafer and multiple first components implemented at the electrostatic chuck;

[0095] Based on the generated measurement data, the characteristics of the wafer relative to the electrostatic chuck are determined; and

[0096] Based on the determined characteristics and by providing a first signal to the electrostatic chuck control system via the controller, at least some of the first components among a plurality of first components can be adjusted while the stage is disengaged.

[0097] 20. The method according to Clause 19, wherein the characteristics of the wafer relative to the electrostatic chuck include the bending of the wafer.

[0098] 21. The method according to any one of Clauses 19 or 20, wherein the plurality of first components include a plurality of electrodes that generate an electric field to modulate the interaction between the wafer and the electrostatic chuck.

[0099] 22. The method according to any one of Clauses 19 to 21, wherein undocking the stage comprises: moving the stage to predetermined coordinates for inspecting the wafer using an electron beam.

[0100] 23. The method according to any one of clauses 19 to 22 further includes:

[0101] Resistance measurement data is generated based on the resistance of the connections between multiple second components and the chip;

[0102] Based on the generated resistance measurement data, determine whether to generate adjustment data for adjusting the resistance of the connection; and

[0103] Based on this determination, a second signal is provided to enable adjustment of at least some of the multiple second components while the stage is being disengaged.

[0104] 24. The method according to Clause 23, wherein providing a second signal to enable adjustment of at least some of the plurality of second components further comprises: enabling a ground pulse generator to generate a pulse to the wafer via a first component of the plurality of second components, the first component being a pin configured to influence the interaction between the wafer and the electrostatic chuck.

[0105] 25. The method according to any one of Clauses 19 or 24 further comprises: providing power from a power source to a system configured to control an electrostatic chuck during a wafer inspection process.

[0106] 26. The method according to any one of Clauses 19 or 25 further includes: docking the stage after the inspection process.

[0107] 27. A system configured to inspect a wafer, comprising:

[0108] The inspection system is configured to manipulate an electron beam used to scan the wafer during the inspection process;

[0109] The stage is configured to be disconnected during the inspection process;

[0110] An electrostatic chuck coupled to a stage, wherein the electrostatic chuck includes multiple components configured to influence the interaction between the wafer and the electrostatic chuck during the inspection process;

[0111] A first sensor is configured to generate measurement data between at least some of a plurality of components and the wafer; and

[0112] The controller includes a circuit system configured to receive measurement data to determine the characteristics of the wafer relative to the electrostatic chuck and generate adjustment data to enable adjustment of at least some of a plurality of components based on the determined characteristics while the stage is being disengaged.

[0113] 28. The system described in Clause 27 further includes:

[0114] The second sensor is configured to generate resistance measurement data that corresponds to the resistance of the connection between multiple pins and the chip. The controller is also configured to receive the resistance measurement data to determine whether to generate adjustment data for adjusting the resistance of the connection.

[0115] 29. A method comprising:

[0116] Power is provided to control the electrostatic chuck during the wafer inspection process while the stage, including the electrostatic chuck, is being disengaged.

[0117] Measurement data is generated based on the interaction between the wafer and multiple first components implemented in an electrostatic chuck;

[0118] The controller determines the characteristics of the wafer relative to the electrostatic chuck based on the generated measurement data.

[0119] Based on the determined characteristics, a first signal is provided to enable adjustment of at least some of the plurality of first components;

[0120] Based on the provided first signal, at least some of the first components among the plurality of first components are adjusted;

[0121] After adjustment, reduce the power; and

[0122] While the stage is being disconnected, at least some of the first components continue to be adjusted.

[0123] 30. The method described under Clause 29 further includes:

[0124] Resistance measurement data is generated based on the resistance of the connections between multiple second components and the chip.

[0125] Based on the generated resistance measurement data, determine whether to generate adjustment data for adjusting the resistance of the connection;

[0126] Based on the determined characteristics, a second signal is provided to enable adjustment of at least some of the plurality of second components; and

[0127] While the stage is being disengaged, at least some of the second components are adjusted based on the provided second signal.

[0128] 31. The method according to any one of Clauses 29 or 30, wherein after the stage is disengaged, the stage is moved to a predetermined position to enable inspection of the wafer using an electron beam.

[0129] A non-transitory computer-readable medium may be provided for storing information for a processor (e.g., Figure 1 The processor of controller 109 Figure 3 The processor of controller 322, Figure 4A Controller 422A or Figure 4B The controller (422B) executes instructions to dynamically adjust the parameters of the electrostatic chuck control system for wafer inspection, image processing, data processing, database management, graphic display, operation of charged particle beam devices or other imaging equipment, control of wafer grounding, and control of wafer grounding position adjustment, etc. Common forms of non-transitory 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, PROM and EPROM, FLASH-EPROM or any other flash memory, NVRAM, cache, registers, any other memory chips or cartridges, and their networked versions.

[0130] The block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer hardware or software products according to various exemplary embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, segment, or portion of code, which includes one or more executable instructions for implementing a specified logical function. It should be understood that in some alternative implementations, the functions indicated in the blocks may occur in a different order than shown in the figures. For example, depending on the function involved, two blocks shown consecutively may be executed substantially simultaneously, or sometimes they may be executed in reverse order. Some blocks may also be omitted. It should also be understood that each block of the block diagram, and combinations of blocks, may be implemented by a system based on dedicated hardware that performs the specified function or action, or by a combination of dedicated hardware and computer instructions.

[0131] It should be understood that the embodiments of the present invention are not limited to the exact constructions described above and illustrated in the accompanying drawings, and various modifications and changes can be made without departing from the scope of the present invention.

Claims

1. An electrostatic chuck control system configured to be utilized during an inspection process of a wafer, the electrostatic chuck control system comprising: an electrostatic chuck of a stage, the stage configured to be undocked during the inspection process, wherein the electrostatic chuck comprises a plurality of components configured to affect an interaction between the wafer and the electrostatic chuck during the inspection process, and wherein the stage is configured to move to a predetermined position after the stage is undocked during the inspection process; a first sensor configured to generate measurement data between at least some of the plurality of components and the wafer; and a controller comprising circuitry configured to receive the measurement data to determine a characteristic of the wafer relative to the electrostatic chuck and generate adjustment data to enable adjustment of at least some of the plurality of components based on the determined characteristic while the stage is undocked.

2. The electrostatic chuck control system of claim 1, further comprising a driver communicatively coupled to the controller and configured to apply control signals to the plurality of components to enable adjustment of the plurality of components.

3. The electrostatic chuck control system of claim 1, wherein the stage is configured to move to the predetermined position during the inspection process to enable a charged particle system to scan the wafer.

4. The electrostatic chuck control system of claim 2, further comprising a power supply to provide power to the driver and the controller.

5. The electrostatic chuck control system of claim 2, further comprising an optical fiber connecting the driver and the controller and configured to transfer data between the driver and the controller.

6. The electrostatic chuck control system of claim 1, wherein the controller comprises a real-time controller.

7. The electrostatic chuck control system of claim 1, wherein the plurality of components comprises a plurality of electrodes configured to affect the interaction between the wafer and the electrostatic chuck by generating an electric field.

8. The electrostatic chuck control system of claim 7, wherein the measurement data generated by the first sensor comprises capacitance measurement data between the plurality of electrodes and the wafer.

9. The electrostatic chuck control system of claim 7, wherein the plurality of electrodes comprises a first set of electrodes and a second set of electrodes, wherein the first set of electrodes and the second set of electrodes are configured to provide data to determine whether the wafer is warped during the inspection process.

10. The electrostatic chuck control system of claim 1, wherein the plurality of components comprises a plurality of pins configured to affect the interaction between the wafer and the electrostatic chuck by transmitting a pulse to the wafer.

11. The electrostatic chuck control system of claim 10, further comprising: A second sensor is configured to generate resistance measurement data corresponding to the resistance of the connection between the plurality of pins and the wafer, wherein the controller is further configured to receive the resistance measurement data to determine whether to generate adjustment data for adjusting the resistance of the connection.

12. The electrostatic chuck control system of claim 10, further comprising a ground pulse generator configured to: generate the pulse to the wafer and receive adjustment data from the controller, such that at least some of the plurality of pins can be adjusted based on the determination. The pulse mentioned therein is a high-voltage pulse.

13. The electrostatic chuck control system of claim 1, wherein the controller is further configured to report errors to an external system based on received measurements.

14. A non-transitory computer-readable medium storing an instruction set executable by a controller of a device to cause the device to perform a method for dynamically adjusting parameters of an electrostatic chuck control system while a stage coupled to an electrostatic chuck is decoupled, the method comprising: While the stage is disengaged for wafer inspection, measurement data is received to determine the characteristics of the wafer relative to the electrostatic chuck, wherein the measurement data is generated based on the interaction between the wafer and a plurality of first components implemented in the electrostatic chuck, and wherein the stage is configured to move to a predetermined position after the stage is disengaged during the wafer inspection. as well as While the stage is being disengaged, at least some of the plurality of first components are adjusted based on the determined characteristics.

15. The non-transitory computer-readable medium of claim 14, wherein the instruction set is executable by the controller of the device to cause the device to further perform: Receive resistance measurement data to determine whether to generate adjustment data for adjusting the resistance of the connections between the plurality of second components and the wafer, wherein the resistance measurement data is generated based on the interaction between the plurality of second components and the wafer; and Based on the determination of whether the adjustment data is generated, at least some of the plurality of second components are adjusted.

16. A method comprising: A stage including an electrostatic chuck is disengaged to perform a wafer inspection process, wherein the stage is configured to move to a predetermined position during the inspection process after the stage is disengaged. Measurement data is generated based on the interaction between the wafer and a plurality of first components implemented at the electrostatic chuck; Based on the generated measurement data, the characteristics of the wafer relative to the electrostatic chuck are determined; as well as Based on the determined characteristics and by providing a first signal to the electrostatic chuck control system via the controller, at least some of the plurality of first components can be adjusted while the stage is disengaged.

17. The method of claim 16, wherein the characteristics of the wafer relative to the electrostatic chuck include the bending of the wafer.

18. The method of claim 16, wherein the plurality of first components comprises a plurality of electrodes that generate an electric field to modulate the interaction between the wafer and the electrostatic chuck.

19. The method of claim 16, wherein undocking the stage comprises: The stage is moved to a predetermined coordinate to inspect the wafer using an electron beam.

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