Continuous scanning system of electron beam detection equipment and electron beam detection equipment

Abstract

The utility model relates to the field of semiconductor manufacturing and detection, in particular to a continuous scanning system of electron beam detection equipment and the electron beam detection equipment. The continuous scanning system comprises a workpiece table used for bearing and driving a to-be-detected piece to move; the laser ruler positioning device is used for outputting a position signal for indicating the position of the workpiece table; the workpiece table driver is used for outputting a scanning starting signal when the workpiece table moves to the initial position of the to-be-scanned area and outputting a scanning ending signal when the workpiece table moves to the ending position of the to-be-scanned area; and the scanning electron microscope is configured to start scanning the surface of the to-be-detected piece when receiving the scanning starting signal and end scanning when receiving the scanning ending signal so as to generate a scanning image of the to-be-detected piece. According to the continuous scanning system provided by the utility model, the synchronization of scanning and moving is improved by synchronously triggering the starting and ending of moving and scanning, and the problem of dislocation of a scanning area is avoided, so that the scanning accuracy is improved.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing and testing, and in particular to a continuous scanning system and an electron beam testing device. Background Technology

[0002] In the semiconductor industry, electron beam defect inspection equipment is used for defect detection during wafer manufacturing. Its main working principle involves transferring the wafer to a stage, where a high-precision stage is positioned to place the area to be inspected under a scanning electron microscope (SEM). The controller then controls the SEM to scan and obtain the corresponding grayscale image. Common scanning path planning methods include step scanning and continuous scanning. In step scanning, the stage moves to the designated position, stops there, and sends a positioning signal. The software then controls the SEM to begin scanning. After completion, the stage moves to the next designated scanning position and scans the image again. In continuous scanning, the stage moves to the starting position of a specific area to be scanned. The central control software issues a movement command, and the stage begins to move continuously at a calculated speed. Simultaneously, the SEM scans continuously perpendicular to the stage's movement direction. Once the entire wafer area has been scanned, movement and scanning stop. Compared to traditional step scanning, continuous scanning reduces stage idle time, significantly increasing the scanning area per unit time of the SEM, thus improving wafer inspection efficiency.

[0003] However, in existing continuous scanning schemes, the synchronization between the two modules, the workpiece stage responsible for movement and the waveform generator responsible for scanning, is poor, resulting in asynchrony between scanning and movement. This leads to problems such as scanning start point offset, incomplete area coverage, or repeated scanning, which in turn affects the accuracy of the detection results. Utility Model Content

[0004] In view of the above problems, this utility model proposes a continuous scanning system and an electron beam detection device for overcoming or at least partially solving the above problems.

[0005] One objective of this invention is to provide a continuous scanning system for an electron beam detection device to improve the synchronization of scanning and movement.

[0006] A further objective of this invention is to reduce testing costs.

[0007] Another further objective of this invention is to improve the accuracy of continuous scanning.

[0008] Another objective of this invention is to provide an electron beam detection device to ensure that scanning and movement are synchronized.

[0009] Specifically, this utility model provides a continuous scanning system for an electron beam detection device, comprising:

[0010] The workpiece stage is used to support and move the workpiece to be inspected.

[0011] The laser ruler positioning device has a position signal output interface, which is used to output a position signal indicating the position of the workpiece stage.

[0012] The workpiece stage driver has a position signal input interface and a digital signal output interface. The position signal input interface is connected to the position signal output interface and is used to receive position signals. The digital signal output interface is used to output a start scanning signal when the workpiece stage moves to the starting position of the area to be scanned and to output a stop scanning signal when the workpiece stage moves to the ending position of the area to be scanned.

[0013] The scanning electron microscope has a digital signal input interface, which is connected to a digital signal output interface and used to receive start scan signal and end scan signal. The scanning electron microscope is configured to start scanning the surface of the workpiece when the start scan signal is received and to end scanning when the end scan signal is received, so as to generate a scanned image of the workpiece.

[0014] Optionally, the laser ruler positioning device includes a laser ruler, which is used to emit laser light waves to the workpiece stage and receive laser light waves reflected back to the laser ruler from the workpiece stage, so as to measure the position of the workpiece stage.

[0015] Optionally, the workpiece stage driver also has a motor phase line interface, which is connected to the workpiece stage and used to send drive signals to the workpiece stage to drive the workpiece stage to move.

[0016] Optionally, the scanning electron microscope includes:

[0017] A waveform generator equipped with a digital signal input interface; and

[0018] An electron gun, connected to a waveform generator via optical fiber, is used to start emitting an electron beam onto the surface of the workpiece when the waveform generator receives a start scanning signal, and to stop emitting the electron beam to end the scan when the waveform generator receives an end scanning signal.

[0019] Optionally, the continuous scanning system also includes:

[0020] The vacuum chamber is used to house the workpiece stage and the electron gun.

[0021] Optionally, the workpiece stage is movably disposed within the vacuum chamber; and

[0022] The electron gun is fixedly installed in the vacuum chamber, and the direction of the electron beam emitted by the electron gun is perpendicular to the direction of movement of the workpiece stage.

[0023] Optionally, the continuous scanning system also includes:

[0024] The control computer, connected to the waveform generator via the PCIe bus, is used to receive scanned images of the device under test.

[0025] Optionally, the control computer is connected to the workpiece stage driver via an EtherCAT bus and is also used to send the start and end positions of the area to be scanned to the workpiece stage driver.

[0026] Optionally, the start scan signal is a high-level signal; and

[0027] The end-scan signal is a low-level signal.

[0028] According to another aspect of the present invention, an electron beam detection device is also provided, comprising:

[0029] The continuous scanning system of any of the above-mentioned electron beam detection devices.

[0030] This invention relates to a continuous scanning system for an electron beam inspection device. This system comprises a workpiece stage, a laser ruler positioning device, a workpiece stage driver, and a scanning electron microscope. The workpiece stage carries and moves the workpiece to be inspected. The laser ruler positioning device outputs a position signal indicating the workpiece stage's position. The workpiece stage driver receives the position signal and outputs start and end scanning signals respectively when the workpiece stage moves to the starting and ending positions of the scanning area. The scanning electron microscope begins scanning the surface of the workpiece upon receiving the start scanning signal and ends scanning upon receiving the end scanning signal to generate a scanned image of the workpiece. This completes the core architecture of the continuous scanning system, achieving strict synchronization between the scanning electron microscope's working cycle and the workpiece stage's movement. This improves the synchronization between scanning and movement, avoiding problems such as scan start point offset, incomplete area coverage, or repeated scanning caused by asynchronous workpiece stage movement and scanning triggering in traditional scanning equipment. This ultimately improves the accuracy of the inspection results.

[0031] Furthermore, in the continuous scanning system of the electron beam inspection equipment of this invention, the laser ruler positioning device includes a laser ruler. The laser ruler emits laser light waves towards the workpiece stage and receives the laser light waves reflected back from the workpiece stage, achieving high-precision position measurement. Therefore, the continuous scanning system of the electron beam inspection equipment of this invention only utilizes the laser light waves received and reflected back from the laser ruler by the workpiece stage, eliminating the need for other modules to analyze and calculate position coordinates, thus achieving accurate measurement of the workpiece stage's position. This significantly saves software and hardware resources, effectively reducing the inspection cost of the electron beam inspection equipment.

[0032] Furthermore, in the continuous scanning system of the electron beam detection device of this invention, the start scanning signal is a high-level signal, and the end scanning signal is a low-level signal. That is, the I / O digital signal is used as the synchronization signal between scanning and movement, achieving precise triggering and stopping of the scan. Therefore, the continuous scanning system of the electron beam detection device of this invention, by using the I / O digital signal as the synchronization signal, improves the response speed and ensures the integrity and accuracy of the scanned image. At the same time, the high and low level signals have strong stability and anti-interference capabilities, reducing false triggering and misoperation during signal transmission to a certain extent, thereby further improving the reliability and stability of the continuous scanning system.

[0033] The above and other objects, advantages and features of this utility model will become more apparent to those skilled in the art from the following detailed description of specific embodiments of this utility model in conjunction with the accompanying drawings. Attached Figure Description

[0034] The following sections will describe some specific embodiments of the present invention in a detailed manner by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or components. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0035] Figure 1 This is a schematic block diagram of an electron beam detection device according to an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of a continuous scanning system of an electron beam detection device according to an embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram of a continuous scanning system of an electron beam detection device according to another embodiment of the present invention. Detailed Implementation

[0038] Exemplary embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art.

[0039] To address the aforementioned problems, this utility model proposes an electron beam detection device. Figure 1 This is a schematic block diagram of an electron beam detection device according to an embodiment of the present invention. Figure 1 As shown, the electron beam detection device of this utility model embodiment generally includes a continuous scanning system 10.

[0040] In this embodiment, the electron beam inspection device may further include a device body for accommodating the device to be inspected, and a continuous scanning system is disposed on the device body. In a specific embodiment, the device to be inspected may include a wafer, a wafer, etc.

[0041] Furthermore, electron beam inspection equipment can be used for detecting defects on the surface of wafers. Additionally, electron beam inspection equipment can also be used for measuring critical dimensions of wafers.

[0042] In addition, such as Figure 1 As shown, the continuous scanning system 10 may include a workpiece stage 100, a laser ruler positioning device 200, a workpiece stage driver 300, a scanning electron microscope 400, and a control computer 600.

[0043] Specifically, the workpiece stage 100 is used to carry the workpiece to be inspected and move it. The laser ruler positioning device 200 is used to measure the position of the workpiece stage 100 and output a position signal indicating the position of the workpiece stage. The workpiece stage driver 300 is used to receive the position signal, output a start scanning signal when the workpiece stage moves to the starting position of the area to be scanned, and output an end scanning signal when the workpiece stage moves to the ending position of the area to be scanned. The scanning electron microscope 500 is used to receive the start scanning signal and the end scanning signal, starts scanning the surface of the workpiece to be inspected when it receives the start scanning signal, and ends scanning when it receives the end scanning signal, so as to generate a scanned image of the workpiece to be inspected.

[0044] Therefore, the electron beam inspection device 1 of this utility model, by setting up a continuous scanning system 10 with a workpiece stage 100, a laser ruler positioning device 200, a workpiece stage driver 300, and a scanning electron microscope 400, establishes the core architecture of the continuous scanning system 10. This achieves strict synchronization between the working cycle of the scanning electron microscope 400 and the movement of the workpiece stage 100, ensuring synchronous scanning and movement. This avoids the problems of scan start point offset, incomplete area coverage, or repeated scanning caused by asynchronous movement of the workpiece stage 100 and scan triggering in traditional scanning equipment, thereby improving the accuracy of the inspection results. The following section combines... Figures 2 to 3 The continuous scanning system of the electron beam detection device in this embodiment will be described in detail.

[0045] Figure 2 This is a schematic diagram of a continuous scanning system of an electron beam detection device according to an embodiment of the present invention.

[0046] like Figure 2 As shown, the continuous scanning system 10 of this embodiment generally includes: a workpiece stage 100, a laser ruler positioning device 200, a workpiece stage driver 300, and a scanning electron microscope 400.

[0047] In this embodiment, the workpiece stage 100 is used to carry the workpiece to be inspected and move it. Specifically, the workpiece to be inspected may include a wafer. During continuous scanning, the wafer may be fixedly mounted on the workpiece stage 100 and move synchronously with the workpiece stage 100. In one specific embodiment, the workpiece stage 100 may include a support portion for carrying the workpiece to be inspected and a motor for driving the support portion to move. After receiving a drive signal, the workpiece stage 100 starts the motor and drives the support portion to move at a calculated speed along the vector direction from the start coordinate to the end coordinate of the scanned area.

[0048] The laser ruler positioning device 200 is used to measure the position of the workpiece stage 100 and output a position signal indicating the position of the workpiece stage. Specifically, the laser ruler positioning device 200 is spaced apart from the workpiece stage 100 and is used to emit laser light waves to the workpiece stage 100 and receive the laser light waves reflected back from the workpiece stage 100. Thus, the laser ruler positioning device 200 can measure the position of the workpiece stage 100 in real time during its movement based on the principle of laser ranging, and has the advantages of high precision and fast response.

[0049] The stage driver 300 receives position signals, outputs a start scanning signal when the stage moves to the starting position of the area to be scanned, and outputs an end scanning signal when the stage moves to the ending position of the area to be scanned. Specifically, during the uniform motion of the stage 100 along the vector direction from the starting coordinate to the ending coordinate of the area to be scanned, the stage 100 transmits a start scanning signal to the scanning electron microscope 400 when it moves to the starting coordinate to indicate the start of scanning, and transmits an end scanning signal to the scanning electron microscope 400 when it moves to the ending coordinate to indicate the end of scanning.

[0050] The scanning electron microscope 500 receives the start and end scanning signals output by the stage driver 300. Upon receiving the start scanning signal, it begins scanning the surface of the workpiece to be inspected, and upon receiving the end scanning signal, it ends the scanning to generate a scanned image of the workpiece. In other words, during a single uniform movement of the stage 100, the scanning electron microscope 500 performs only one start and one end scanning operation, thus achieving continuous scanning to generate a scanned image of the workpiece.

[0051] The continuous scanning system 10 of the electron beam detection device 1 of this utility model rapidly and accurately feeds back the position of the workpiece stage 100 during its rapid movement via the laser ruler positioning device 200. The workpiece stage driver 300 outputs start and end scanning signals respectively when the workpiece stage 100 moves to the starting and ending positions of the area to be scanned. The scanning electron microscope 400 starts scanning in response to the start scanning signal and ends scanning in response to the end scanning signal. This ensures that the scanning electron microscope 400 can scan synchronously with the uniform movement of the workpiece stage 100, without any delay or misalignment, thus guaranteeing the accuracy of continuous scanning.

[0052] Figure 3 This is a schematic diagram of a continuous scanning system of an electron beam detection device according to another embodiment of the present invention.

[0053] like Figure 3 As shown, the laser ruler positioning device 200 has a position signal output interface 220. Correspondingly, the workpiece stage driver 300 has a position signal input interface 310. Specifically, the position signal output interface 220 is used to output a position signal indicating the position of the workpiece stage 100. The position signal input interface 310 is connected to the position signal output interface 220 and is used to receive position signals. Thus, the position of the workpiece stage 100 measured by the laser ruler positioning device 200 can be stably transmitted to the workpiece stage driver 300, so that the workpiece stage driver 300 can promptly acquire the position of the workpiece stage 100 and determine the position of the workpiece stage 100 based on its position.

[0054] like Figure 3 As shown, the stage driver 300 also has a digital signal output interface 320. Correspondingly, the scanning electron microscope 400 has a digital signal input interface 411. Specifically, the digital signal output interface 320 is used to output a start scanning signal when the stage 100 moves to the starting position of the area to be scanned, and to output an end scanning signal when the stage 100 moves to the ending position of the area to be scanned. In addition, the digital signal input interface 411 is connected to the digital signal output interface 320 and is used to receive the start scanning signal and the end scanning signal. Thus, the stage driver 300 can transmit the start scanning signal and the end scanning signal to the scanning electron microscope 400 according to the moving position of the stage 100.

[0055] Furthermore, in this embodiment, the scanning electron microscope 400 is configured to begin scanning the surface of the workpiece upon receiving a start scanning signal and to end scanning upon receiving an end scanning signal, thereby generating a scanned image of the workpiece. In other words, the scanning electron microscope 400 synchronously begins scanning when the stage 100 moves to the starting position of the area to be scanned and synchronously ends scanning when the stage 100 moves to the ending position of the area to be scanned. Thus, the scanning electron microscope 400 can synchronously trigger the start and end of scanning based on the moving position of the stage 100, achieving synchronization between scanning and movement.

[0056] The continuous scanning system 10 of the electron beam inspection device 1 of this utility model, by setting up a workpiece stage 100, a laser ruler positioning device 200, a workpiece stage driver 300, and a scanning electron microscope 400, utilizes the workpiece stage 100 to carry and move the workpiece to be inspected. The laser ruler positioning device 200 outputs a position signal indicating the position of the workpiece stage 100. The workpiece stage driver 300 receives the position signal and outputs a start scanning signal and an end scanning signal respectively when the workpiece stage 100 moves to the start position and end position of the scanning area. The scanning electron microscope 400 starts scanning the surface of the workpiece to be inspected when it receives the start scanning signal and ends scanning when it receives the end scanning signal to generate a scanned image of the workpiece to be inspected. This establishes the core architecture of the continuous scanning system 10, achieving strict synchronization between the working cycle of the scanning electron microscope 400 and the movement of the workpiece stage 100, improving the synchronization between scanning and movement. This avoids the problems of scanning start point offset, incomplete area coverage, or repeated scanning caused by asynchronous movement of the workpiece stage 100 and scanning triggering in traditional scanning equipment, thereby improving the accuracy of the inspection results.

[0057] In some embodiments, such as Figure 2 and Figure 3As shown, both the start and end scan signals can be I / O digital signals. Therefore, the stage driver 300 and the scanning electron microscope 400 can communicate via I / O digital signals, improving transmission efficiency and response speed, thus ensuring the accuracy of continuous scanning.

[0058] In one specific embodiment, the start scan signal can be a high-level signal, and the end scan signal can be a low-level signal. That is, in the continuous scanning system 10 of the electron beam detection device 1 of this utility model, when the workpiece stage 100 moves to the starting position of the area to be scanned, the workpiece stage driver 300 sets the I / O digital signal between itself and the scanning electron microscope 400 to a high level. After receiving the high level, the scanning electron microscope 400 starts scanning. When the workpiece stage 100 moves to the ending position of the area to be scanned, the workpiece stage driver 300 sets the I / O digital signal between itself and the scanning electron microscope 400 to a low level. After receiving the low level, the scanning electron microscope 400 ends scanning.

[0059] Therefore, the continuous scanning system 10 of the electron beam inspection device 1 of this invention, by using I / O digital signals as synchronization signals, enables the scanning electron microscope 400 to synchronously trigger the start and end of scanning according to the moving position of the workpiece stage 100, achieving synchronization between scanning and movement, improving response speed, and enabling precise triggering and stopping of scanning, thus ensuring the integrity and accuracy of the scanned image. Simultaneously, the high and low level signals exhibit strong stability and anti-interference capabilities, reducing false triggering and misoperation during signal transmission to a certain extent, thereby further improving the reliability and stability of the continuous scanning system 10.

[0060] In some embodiments, such as Figure 2 and Figure 3 As shown, the continuous scanning system 10 of the electron beam inspection device 1 of this utility model may further include a control computer 600. Specifically, the control computer 600 and the workpiece stage driver 300 are connected via an EtherCAT (Ethernet for Control Automation Technology) bus. It should be noted that the EtherCAT bus is a fieldbus system based on Ethernet, which can realize control automation.

[0061] In this embodiment, the control computer 600 is also used to send the start and end positions of the area to be scanned to the workpiece stage driver 300. That is, the control computer 600 communicates with the workpiece stage driver 300 via an EtherCAT bus.

[0062] Therefore, the continuous scanning system 10 of the electron beam detection device 1 of this utility model realizes nanosecond-level communication between the control computer 600 and the workpiece stage driver 300 through the EtherCAT bus, which effectively supports the control computer to send the start and end positions of the scanned area to the workpiece stage driver efficiently and quickly, improves the transmission efficiency, and enhances the reliability and maintainability of the system.

[0063] In some embodiments, such as Figure 3 As shown, the workpiece stage driver 300 also has a motor phase line interface 330, which is connected to the workpiece stage 100 and used to send drive signals to the workpiece stage 100 to drive the workpiece stage 100 to move.

[0064] Specifically, the motor phase line interface 330 is connected to the workpiece stage 100 via the motor phase line, so that the workpiece stage driver 300 can transmit drive signals to the workpiece stage 100 using the motor phase line interface 330 and the motor phase line.

[0065] In one specific embodiment, the workpiece stage 100 can be a servo motor or a linear motor, and the motor phase interface can support high-precision driving of the servo motor or linear motor. Additionally, the drive signal can be used to instruct the workpiece stage 100 to move at a preset speed along the vector direction from the start coordinate to the end coordinate of the area to be scanned.

[0066] For example, after the control computer 600 sends the start and end positions of the area to be scanned to the workpiece stage driver 300 via the EtherCAT bus, the workpiece stage driver 300 first transmits a drive signal to the workpiece stage 100 via the motor phase line interface 330 to drive the workpiece stage 100 to quickly position itself to the start position of the area to be scanned, and then drives the workpiece stage 100 to move at a constant speed to the end position of the area to be scanned.

[0067] Therefore, the continuous scanning system 10 of the electron beam detection device 1 of this utility model, by setting the motor phase line interface 330 connected to the workpiece stage 100 on the workpiece stage driver 300 and sending a drive signal to the workpiece stage 100 to drive the workpiece stage 100 to move, realizes accurate control of the position and moving speed of the workpiece stage 100, which facilitates the control and driving of the workpiece stage 100 to move at a uniform speed, thereby improving the accuracy of the scanned image of the workpiece to be inspected.

[0068] In some embodiments, such as Figure 3 As shown, the scanning electron microscope 400 may include a waveform generator 410 and an electron gun 420. Specifically, the electron gun 420 and the waveform generator 410 are connected via optical fiber to achieve fast communication.

[0069] like Figure 3As shown, the waveform generator 410 is provided with a digital signal input interface 411 to connect with the digital signal output interface 320 on the workpiece stage driver 300, so as to receive the start scan signal and the end scan signal.

[0070] In this embodiment, the electron gun 420 is used to start emitting an electron beam toward the surface of the object to be inspected when the waveform generator 410 receives the start scan signal, and to stop emitting the electron beam to end the scan when the waveform generator 410 receives the end scan signal.

[0071] Specifically, the electron gun 420 scans the surface of the workpiece under test with a high-energy electron beam, collects and analyzes signals such as secondary electrons and backscattered electrons generated by the interaction between electrons and the workpiece under test, thereby achieving accurate measurement of the surface morphology, size or defects of the workpiece under test.

[0072] Therefore, the continuous scanning system 10 of the electron beam detection device 1 of this utility model realizes communication between the electron gun 420 and the waveform generator 410 through optical fiber, realizing signal transmission with anti-electromagnetic interference, high bandwidth and low delay, avoiding the influence of electromagnetic noise, ensuring the communication efficiency and communication stability between the electron gun 420 and the waveform generator 410, thereby further ensuring strict synchronization between scanning and movement.

[0073] In some embodiments, such as Figure 2 and Figure 3 As shown, the control computer 600 and the waveform generator 410 are connected via a PCIe (Peripheral Component Interconnect express) bus to receive scanned images of the device under test. In other words, the control computer 600 communicates with the waveform generator 410 via the PCIe bus. It should be noted that the PCIe bus is a high-speed serial computer expansion bus capable of high-speed data transmission.

[0074] Therefore, the continuous scanning system 10 of the electron beam detection device 1 of this invention can accurately acquire the images obtained by continuous scanning, so as to improve the detection efficiency and accuracy of the electron beam detection device 1.

[0075] In some embodiments, such as Figure 3 As shown, the continuous scanning system 10 of the electron beam inspection device 1 of this utility model may further include a vacuum chamber 500. Specifically, the vacuum chamber 500 is used to accommodate the workpiece stage 100 and the electron gun 420 to create a high-vacuum scanning environment.

[0076] Therefore, the continuous scanning system 10 of the electron beam inspection device 1 of this invention, by setting up a vacuum chamber, effectively reduces the influence of external vibration and temperature changes on the scanning results, ensures the stability of the electron beam incident angle, avoids the problem of image ghosting caused by vibration or temperature changes, and improves the accuracy of the scanned image. At the same time, the high-vacuum scanning environment created reduces the contamination of the workpiece stage 100 and electron gun 420 by water vapor and dust in the atmospheric environment, extends the maintenance cycle of the electron beam inspection device 1, and reduces the operating cost.

[0077] In some embodiments, such as Figure 2 and Figure 3 As shown, the workpiece stage 100 is movably disposed within the vacuum chamber 500. The electron gun 420 is fixedly disposed within the vacuum chamber 500, and the emission direction of the electron beam emitted by the electron gun 420 is perpendicular to the moving direction of the workpiece stage 100.

[0078] Specifically, the workpiece stage 100 can move linearly in the horizontal direction within the vacuum chamber 500. The electron gun 420 is positioned above the workpiece stage 100 and emits an electron beam vertically downwards, so that the scanning direction of the electron beam is orthogonal to the moving direction of the workpiece stage. This avoids geometric distortion caused by oblique scanning, improves the imaging quality of the scanned image, and provides a precise data basis for subsequent image analysis algorithms (such as edge detection and defect matching) of the electron beam detection device 1.

[0079] In some embodiments, such as Figure 3 As shown, the laser ruler positioning device 200 may include a laser ruler 210, which is used to emit laser light waves to the workpiece stage 100 and receive the laser light waves reflected back to the laser ruler 210 from the workpiece stage 100, so as to measure the position of the workpiece stage 100. That is, the laser ruler positioning device 200 uses the laser ruler 210 to measure the position of the workpiece stage 100, thereby realizing the effective acquisition of the position of the workpiece stage 100.

[0080] Specifically, the laser ruler 210 can be set on the outside of the vacuum chamber 500, and the laser wave emitting port and the laser wave receiving port of the laser ruler 210 can both be fitted to the outer wall surface of the vacuum chamber 500 to emit laser waves to the workpiece stage 100 inside the vacuum chamber 500 and receive the laser waves reflected back from the workpiece stage 100 inside the vacuum chamber 500.

[0081] Therefore, the continuous scanning system 10 of the electron beam inspection device 1 of this utility model only uses the workpiece stage 100 to receive and reflect the laser light wave back to the laser ruler 210, without the need for other modules to analyze and calculate the position coordinate value, so as to realize the measurement of the position of the workpiece stage 100, which greatly saves software and hardware resources and effectively reduces the inspection cost of the electron beam inspection device 1.

[0082] In one specific embodiment, the continuous scanning system 10 of the electron beam inspection device 1 of this utility model can be used for continuous scanning when detecting defects on the surface of a wafer.

[0083] Specifically, during the use of the continuous scanning system 10, the control computer 600 first sends the start coordinates and end coordinates of the wafer to be scanned area to the workpiece stage driver 300, and the workpiece stage driver 300 drives the workpiece stage 100 to move.

[0084] The laser ruler positioning device 200 measures the real-time position of the workpiece stage 100 and transmits the position signal indicating the real-time position of the workpiece stage 100 to the workpiece stage driver 300.

[0085] The stage driver 300 performs closed-loop control and position coordinate judgment based on the real-time position of the stage 100. When the stage 100 moves to the starting coordinate of the wafer to be scanned area, it sets the I / O digital signal between the stage driver 300 and the scanning electron microscope 400 to a high level. The scanning electron microscope 400 starts scanning after receiving the high-level signal.

[0086] The stage driver 300 continues to drive the stage 100 to move at a constant speed along the vector direction from the starting coordinate to the ending coordinate until the stage 100 moves to the ending coordinate. At this point, the stage driver 300 sets the I / O digital signal between itself and the scanning electron microscope 400 to a low level. The scanning electron microscope 400 ends the scanning after receiving the low-level signal.

[0087] The scanning electron microscope 400 transmits the scanned images obtained from continuous scanning to files in the control computer 600.

[0088] Therefore, the continuous scanning system 10 of the electron beam detection device 1 of this utility model, by setting up a workpiece stage 100, a laser ruler positioning device 200, a workpiece stage driver 300, a scanning electron microscope 400 and a control computer 600, establishes the core architecture of the continuous scanning system 10. This achieves strict synchronization between the working cycle of the scanning electron microscope 400 and the movement of the workpiece stage 100, improving the synchronization between scanning and movement. This avoids the problems of scanning start point offset, incomplete area coverage or repeated scanning caused by asynchronous movement of the workpiece stage 100 and scanning triggering in traditional scanning equipment, thereby improving the accuracy of the detection results.

[0089] Furthermore, in the continuous scanning system 10 of the electron beam detection device 1 of this invention, the response speed is improved by using I / O digital signals as synchronization signals, ensuring the integrity and accuracy of the scanned image. Simultaneously, the high and low level signals exhibit strong stability and anti-interference capabilities, reducing false triggering and malfunctions during signal transmission to a certain extent, thereby further improving the reliability and stability of the continuous scanning system 10.

[0090] Therefore, those skilled in the art should recognize that although many exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and recognized as covering all such other variations or modifications.

Claims

1. A continuous scanning system of an electron beam inspection apparatus, characterized by, include: A workpiece stage is used to support the workpiece to be inspected and to move the workpiece to be inspected. A laser ruler positioning device has a position signal output interface, which is used to output a position signal indicating the position of the workpiece stage. A workpiece stage driver has a position signal input interface and a digital signal output interface. The position signal input interface is connected to the position signal output interface and is used to receive the position signal. The digital signal output interface is used to output a start scanning signal when the workpiece stage moves to the starting position of the area to be scanned and to output a stop scanning signal when the workpiece stage moves to the ending position of the area to be scanned. A scanning electron microscope has a digital signal input interface connected to a digital signal output interface and used to receive a start scan signal and a stop scan signal. The scanning electron microscope is configured to start scanning the surface of the object under test when the start scan signal is received, and to stop scanning when the stop scan signal is received, so as to generate a scanned image of the object under test.

2. The continuous scanning system of the electron beam detection device according to claim 1, characterized in that, The laser ruler positioning device includes a laser ruler, which is used to emit laser light waves to the workpiece stage and receive laser light waves reflected back to the laser ruler from the workpiece stage, so as to measure the position of the workpiece stage.

3. The continuous scanning system of the electron beam detection device according to claim 1, characterized in that, The workpiece stage driver also has a motor phase line interface, which is connected to the workpiece stage and used to send a drive signal to the workpiece stage to drive the workpiece stage to move.

4. The continuous scanning system of electron beam inspection apparatus according to claim 1, wherein, The scanning electron microscope includes: A waveform generator, which is equipped with the aforementioned digital signal input interface; and An electron gun, connected to the waveform generator via an optical fiber, is used to start emitting an electron beam toward the surface of the object to be tested when the waveform generator receives the start scan signal, and to stop emitting the electron beam to end the scan when the waveform generator receives the end scan signal.

5. The continuous scanning system of electron beam inspection apparatus according to claim 4, wherein, The continuous scanning system also includes: A vacuum chamber for housing the workpiece stage and the electron gun.

6. The continuous scanning system of the electron beam detection device according to claim 5, characterized in that, The workpiece stage is movably disposed within the vacuum chamber; and The electron gun is fixedly installed in the vacuum chamber, and the direction of the electron beam emitted by the electron gun is perpendicular to the direction of movement of the workpiece stage.

7. The continuous scanning system of electron beam inspection apparatus according to claim 4, wherein The continuous scanning system also includes: A control computer, connected to the waveform generator via a PCIe bus, is used to receive scanned images of the device under test.

8. The continuous scanning system of the electron beam detection device according to claim 7, characterized in that, The control computer is connected to the workpiece stage driver via an EtherCAT bus and is also used to send the start position and the end position of the area to be scanned to the workpiece stage driver.

9. The continuous scanning system of electron beam inspection apparatus according to claim 1, wherein: the start scan signal is a high level signal; and the end scan signal is a low level signal.

10. An electron beam detecting apparatus characterized by comprising: comprising: the continuous scanning system of electron beam inspection apparatus according to any one of claims 1 to 9.

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