Scanning compensation method, system and electronic equipment based on vibration relaxation

Abstract

The present application provides a scanning compensation method, system and electronic device based on vibration relaxation, including: based on a start positioning signal, generating a positioning action instruction; based on the positioning action instruction, controlling the movement of the workpiece stage and judging whether it moves to the vibration compensation range; when the workpiece stage moves to the vibration compensation range, controlling the workpiece stage to move in the form of a vibration of a preset vibration relaxation model to determine the first position deviation during the movement of the workpiece stage; based on the first position deviation, generating a scanning compensation signal; performing electron beam scanning based on the scanning compensation signal, the scanning compensation signal drives the electron beam to move relative to the workpiece stage during the electron beam scanning process. The scanning compensation method based on vibration relaxation of the present application reduces the image quality degradation problem caused by vibration relaxation in electron beam scanning imaging by optimizing the positioning process of the workpiece stage, improves the scanning image resolution, and improves the imaging speed and the overall production capacity of the equipment.

Description

Technical Field

[0001] The present application relates to the technical field of electron beam scanning imaging, and in particular to a scanning compensation method, system and electronic equipment based on vibration relaxation. Background Art

[0002] Electron beam scanning imaging equipment is mainly composed of scanning electron microscope, electron beam defect detection equipment, electron beam key dimension measurement equipment, etc. During the scanning imaging process of the electron beam scanning imaging equipment, when the sample area to be scanned is not covered by the electron beam scanning range (or field of view), the workpiece stage needs to carry the sample and move it to the specified target position.

[0003] After the workpiece stage reaches the vicinity of the target position, it needs to go through a process from motion to relative stillness. During this process, the workpiece stage position relative to the target position shows a reciprocating motion with a gradually attenuated amplitude (or called damped vibration, vibration relaxation, etc.). During this period, since the sample position is not fixed, it is impossible to obtain a normal scanning image. This process usually takes hundreds of milliseconds to several seconds (called stabilization time).

[0004] For application scenarios that require higher imaging speeds, the detection efficiency will be greatly reduced, affecting the overall scanning speed (or production capacity) of the equipment. According to publicly available information, there is currently no reliable technical solution that can effectively utilize the stabilization time. Existing electron beam scanning imaging equipment mainly reduces the impact of vibration relaxation on scanning imaging by waiting for the workpiece stage to enter a quasi-stationary state (the vibration amplitude is less than a certain level, such as 10nm or 3nm), isolating external vibrations, or performing image compensation for the system's inherent (non-changing motion state) vibrations. However, the above method fails to utilize the time loss during the vibration relaxation of the workpiece stage, and cannot effectively improve the efficiency of electron beam scanning imaging. Summary of the invention

[0005] The present application provides a scanning compensation method, system and electronic device based on vibration relaxation, which are used to solve the technical problem that the electron beam scanning imaging technology in the prior art fails to utilize the time loss during the vibration relaxation process of the workpiece table and cannot effectively improve the efficiency of electron beam scanning imaging.

[0006] According to a first aspect of the present application, a scanning compensation method based on vibration relaxation is provided, comprising: generating a positioning action instruction based on a start positioning signal; controlling the movement of a workpiece stage and determining whether it moves to a vibration compensation range based on the positioning action instruction; when the workpiece stage moves to the vibration compensation range, controlling the workpiece stage to move in a vibration form of a preset vibration relaxation model to determine a first position deviation during the movement of the workpiece stage; generating a scanning compensation signal based on the first position deviation; performing electron beam scanning based on the scanning compensation signal, wherein the scanning compensation signal drives the electron beam to move relative to the workpiece stage during the electron beam scanning process.

[0007] In some embodiments, the positioning action instruction includes a starting position and a target position of the workpiece stage, the starting position is the current position of the center of the workpiece stage, and the target position is the position of the center of the electron beam scanning field of view, and based on the positioning action instruction, controlling the movement of the workpiece stage and determining whether it moves to the vibration compensation range includes: based on the starting position and the target position of the workpiece stage, controlling the workpiece stage to move toward the target position to determine a second position deviation during the movement of the workpiece stage; and determining that the workpiece stage moves to the vibration compensation range when the second position deviation is less than a preset threshold.

[0008] In some embodiments, the vibration compensation range is determined based on a scanning range of the electron beam scanning field of view and a vibration range corresponding to the vibration relaxation model.

[0009] In some embodiments, when the workpiece stage moves to the vibration compensation range, the workpiece stage is controlled to move in the vibration form of a preset vibration relaxation model to determine a first position deviation during the movement of the workpiece stage, including: in the process of controlling the workpiece stage to move in the vibration form of a preset vibration relaxation model, acquiring the current position of the center of the workpiece stage in real time; based on the current position of the center of the workpiece stage and the target position, determining the current first position deviation.

[0010] In some embodiments, before controlling the workpiece stage to move in the vibration form of a preset vibration relaxation model to determine the first position deviation during the movement of the workpiece stage, the method also includes: controlling the workpiece stage to perform simulated movement to obtain the real-time position of the center of the workpiece stage at any time; determining the position deviation corresponding to any time based on the target position and the real-time position of the center of the workpiece stage at any time; and fitting the vibration relaxation model composed of time and position deviation according to any time and its corresponding position deviation.

[0011] In some embodiments, generating a scanning compensation signal based on the first position deviation includes: determining vibration compensation parameters at any moment based on the current first position deviation and a preset vibration compensation model; determining a vibration compensation waveform according to the vibration compensation parameters; and generating a scanning compensation signal based on the vibration compensation waveform.

[0012] In some embodiments, before generating a scanning compensation signal based on the first position deviation, the method further includes: determining the vibration compensation model based on the vibration relaxation model, wherein corresponding vibration compensation parameters in the vibration compensation model correspond to corresponding position deviations in the vibration relaxation model.

[0013] According to a second aspect of the present application, a scanning compensation system based on vibration relaxation is provided, comprising: an industrial computer, for generating a positioning action instruction based on a start positioning signal; a workpiece stage controller, for controlling the movement of the workpiece stage and determining whether it moves to a vibration compensation range based on the positioning action instruction, and for controlling the workpiece stage to move in a vibration form of a preset vibration relaxation model when the workpiece stage moves to the vibration compensation range, so as to determine a first position deviation during the movement of the workpiece stage; a drive compensation module, for generating a scanning compensation signal based on the first position deviation; and a scanning module, for scanning based on the scanning compensation signal, wherein the scanning compensation signal drives the electron beam to move relative to the workpiece stage during electron beam scanning.

[0014] In some embodiments, the driving compensation module includes a dynamic compensation circuit module, a scanning waveform generator and a driving deflector; the dynamic compensation circuit module is configured with a vibration compensation model for determining vibration compensation parameters based on the first position deviation; the scanning waveform generator is used to determine a vibration compensation waveform based on the vibration compensation parameters; and the driving deflector is used to generate a scanning compensation signal based on the vibration compensation waveform.

[0015] According to the third aspect of the present application, an electronic device is provided, characterized in that it includes: one or more processors, a memory and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include a method for executing the above-mentioned vibration relaxation-based scanning compensation method.

[0016] In summary, the scanning compensation method, system and electronic device based on vibration relaxation provided by the present application have at least the following beneficial effects:

[0017] In the scanning compensation method based on vibration relaxation of the present application, it optimizes the workpiece stage positioning process, and in the positioning process of the workpiece stage, the difference between the current position and the target position of the center of the workpiece stage (i.e., the first position deviation) is obtained in real time, and a scanning compensation signal is generated based on the first position deviation, so that in the electron beam scanning process, the electron beam is driven to move relative to the workpiece stage based on the generated scanning compensation signal. And because the distance that the scanning compensation signal drives the electron beam to move relative to the workpiece stage is consistent with the first position deviation, the compensation effect in the positioning process is achieved, thereby reducing the image quality degradation problem caused by vibration in the electron beam scanning imaging, improving the image resolution, and improving the imaging speed and the overall production capacity of the equipment. At the same time, the time spent in the workpiece stage positioning process by the prior art is greatly reduced, so that the scanning can be started when the positioning window range is larger than the scanning range of the prior art, saving the waiting time in the scanning process. The present application is applicable to the compensation method for vibration during the vibration relaxation process of the workpiece stage in the commonly used step-by-step imaging mode, which can effectively improve the detection speed and production capacity of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 A flowchart of a scanning compensation method based on vibration relaxation provided in an embodiment of the present application;

[0020] Figure 2 A vibration curve diagram of the reciprocating vibration of a workpiece table around a zero point in a scanning compensation method based on vibration relaxation provided in an embodiment of the present application;

[0021] Figure 3 A vibration curve diagram of a workpiece stage vibrating with an overall negative deviation relative to a zero point in a scanning compensation method based on vibration relaxation provided in an embodiment of the present application;

[0022] Figure 4 A schematic diagram of a normal scanning image in a vibration-free state in a scanning compensation method based on vibration relaxation provided in an embodiment of the present application;

[0023] Figure 5 A schematic diagram of a scanning image under a vibration state in a scanning compensation method based on vibration relaxation provided in an embodiment of the present application;

[0024] Figure 6A schematic diagram of a typical scanning mode of electron beam scanning imaging in a scanning compensation method based on vibration relaxation provided in an embodiment of the present application;

[0025] Figure 7 A schematic diagram of an electron beam scanning imaging device in a scanning compensation method based on vibration relaxation provided in an embodiment of the present application;

[0026] Figure 8 It is a flow chart of the positioning and scanning process of the workpiece stage in the prior art in the embodiment of the present application;

[0027] Fig. 9 A structural diagram of a scanning compensation system based on vibration relaxation provided in an embodiment of the present application;

[0028] Fig.10 A structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to make the above and other features and advantages of the present application more clear, the present application is further described below in conjunction with the accompanying drawings. It should be understood that the specific embodiments given herein are for the purpose of explaining to those skilled in the art and are only exemplary and not restrictive.

[0030] In the following description, many specific details are set forth to provide a thorough understanding of the present application. However, it is apparent to those skilled in the art that specific details need not be adopted to practice the present application. In other cases, well-known steps or operations are not described in detail to avoid blurring the present application.

[0031] The vibration relaxation-based scanning compensation method provided in the embodiment of the present application can be executed by the vibration relaxation-based scanning compensation system provided in the embodiment of the present application, and the system can be configured in an electronic device.

[0032] Refer to the attached Figure 1 As shown, the present application provides a scanning compensation method based on vibration relaxation, which includes steps 301-305.

[0033] Step 301: Generate a positioning action instruction based on a start positioning signal.

[0034] Specifically, a start positioning signal can be first obtained through the host computer or the central control computer. After obtaining the start positioning signal, the positioning information of the workpiece stage can be collected through the corresponding sensor and sent to the host computer or the central control computer. Then, the host computer or the central control computer generates a positioning action instruction based on the received positioning information of the workpiece stage and sends it to the dynamic compensation circuit module or the workpiece stage controller.

[0035] In addition, the positioning action instruction includes at least parameters such as the positioning information of the workpiece stage and the movement time of the workpiece stage. The positioning information of the workpiece stage may specifically include parameters such as the starting position and target position of the workpiece stage, wherein the starting position is the current position of the center of the workpiece stage, and the target position is the position of the center of the electron beam scanning field of view.

[0036] Step 302: Based on the positioning action instruction, control the movement of the workpiece stage and determine whether it moves to the vibration compensation range.

[0037] In some embodiments, the vibration compensation range is determined based on a scanning range of the electron beam scanning field of view and a vibration range corresponding to a vibration relaxation model.

[0038] For example, the maximum field of view (scanning range, FOV) of an electron beam scanning imaging device is represented by F max , that is, the scanning range of the electron beam scanning field is F max (usually up to tens of microns to several millimeters); the imaging field of the actual imaging setting is represented as F img , the scanning range F of the electron beam scanning field max With imaging field F img The difference between the two can determine the maximum positioning window range (also called the ideal maximum compensation range) that can achieve vibration compensation. max , d max This is the vibration range corresponding to the vibration relaxation model. Then, according to the maximum positioning window range d max Determine the vibration compensation range D max , that is, D max The range must include d max range.

[0039] Step 303 : When the workpiece stage moves to the vibration compensation range, the workpiece stage is controlled to move in a vibration form of a preset vibration relaxation model to determine a first position deviation during the movement of the workpiece stage.

[0040] Refer to the attached Figure 8As shown, according to some prior art, before the electron beam scanning imaging device performs scanning imaging, it is necessary to first move the area to be scanned of the sample within the electron beam imaging range and then start the scanning. The electron beam imaging range generally selects the electron beam scanning field of view. Moving the sample within the electron beam imaging range means moving the area to be scanned of the sample to coincide with the center of the electron beam scanning field of view. The positioning execution process of this process can be represented by process 200, including: 205 sending a start instruction from the host computer; 210 controlling the workpiece stage to displace to a specified position or target position; 215 when the workpiece stage reaches near the specified position, the position sensor feeds back position information; 220 determining whether the position deviation is less than the specified value d; 230 when the position deviation is not less than the specified value d, the workpiece stage is fine-tuned according to the position sensor; 230 when the position deviation is less than the specified value d, the positioning is completed; 235 starting the electron beam scanning imaging.

[0041] It can be seen from this that the prior art fails to effectively compensate for vibration relaxation during the positioning process of the workpiece stage. It is necessary to start scanning imaging only after the position of the workpiece stage is adjusted in place. During the position adjustment process of the workpiece stage, the corresponding steps in steps 215 - 230 need to be repeatedly executed, and the required stabilization time will affect the overall scanning imaging speed or production capacity of the electron beam scanning imaging device. Refer to the appendix Figure 2 As shown, within the positioning window range value d1 > d2, the corresponding stabilization time t1 < t2. It can be seen that the larger the positioning window range d, the shorter the required time. Since d is generally set at the nanometer level, the corresponding stabilization time t is usually in the order of hundreds of milliseconds to seconds.

[0042] In order to reduce the time consumed by process 200 in the prior art during the positioning process of the workpiece stage, the scanning compensation method based on vibration relaxation in this application optimizes the positioning process of the workpiece stage so that scanning can be started during the positioning process of the workpiece stage to save waiting time.

[0043] In some embodiments, when the workpiece stage moves to the vibration compensation range, the workpiece stage is controlled to move in the vibration form of a preset vibration relaxation model to determine the first position deviation during the movement of the workpiece stage, including: during the process of controlling the workpiece stage to move in the vibration form of a preset vibration relaxation model, the current position of the center of the workpiece stage is obtained in real time; based on the current position of the center of the workpiece stage and the target position, the current first position deviation is determined.

[0044] Step 304, generating a scanning compensation signal based on the first position deviation.

[0045] It can be understood that the first position deviation is the difference between the current position of the center of the workpiece stage and the target position, and the scanning compensation signal is a scanning signal with a compensation function.

[0046] Step 305 , performing electron beam scanning based on the scanning compensation signal, wherein the scanning compensation signal drives the electron beam to move relative to the workpiece stage during the electron beam scanning process.

[0047] In the scanning compensation method based on vibration relaxation of the present application, it optimizes the workpiece stage positioning process, and in the positioning process of the workpiece stage, the difference between the current position and the target position of the center of the workpiece stage (i.e., the first position deviation) is obtained in real time, and a scanning compensation signal is generated based on the first position deviation, so that in the electron beam scanning process, the electron beam is driven to move relative to the workpiece stage based on the generated scanning compensation signal. And because the distance that the scanning compensation signal drives the electron beam to move relative to the workpiece stage is consistent with the first position deviation, the compensation effect in the positioning process is achieved, thereby reducing the image quality degradation problem caused by vibration in the electron beam scanning imaging, improving the image resolution, and improving the imaging speed and the overall production capacity of the equipment. At the same time, the time spent in the workpiece stage positioning process by the prior art is greatly reduced, so that the scanning can be started when the positioning window range is larger than the scanning range of the prior art, saving the waiting time in the scanning process. The present application is applicable to the compensation method for vibration during the vibration relaxation process of the workpiece stage in the commonly used step-by-step imaging mode, which can effectively improve the detection speed and production capacity of the equipment.

[0048] The following is a specific implementation process of a scanning compensation method based on vibration relaxation provided by the present application, and the method includes steps 401-405.

[0049] Step 401: Generate a positioning action instruction based on a start positioning signal.

[0050] Step 402, based on the starting position and target position of the workpiece stage, control the workpiece stage to move toward the target position to determine a second position deviation during the movement of the workpiece stage; when the second position deviation is less than a preset threshold, determine that the workpiece stage moves to a vibration compensation range.

[0051] For example, to ensure the validity of the judgment, the second position deviation value D may be a set of data (D1, D2...) collected within a certain period of time (sampling period). When the maximum value is less than a preset threshold value d (the preset threshold value d is also called the positioning window size), it can be determined that the workpiece stage moves to the vibration compensation range. During the movement of the workpiece stage, the second position deviation usually shows a gradually decreasing trend.

[0052] It should be noted that, refer to the attached Figure 4-5 As shown in the figure, when the workpiece stage has not moved to the vibration compensation range, the scanning imaging starts, which may cause image deviation due to the large deviation of the workpiece stage, and the phenomenon presented by the image positioning deviation may also have the characteristics of oscillation relaxation attenuation. The selection of the sampling period needs to take into account the mechanical vibration period that may affect the imaging.

[0053] It can be understood that when the second position deviation is less than the preset threshold, it is determined that the workpiece stage has not moved to the vibration compensation range, and at the same time, the steps of controlling the movement of the workpiece stage and determining whether it moves to the vibration compensation range are continued.

[0054] For example, when the workpiece stage moves to the vicinity of the vibration compensation range, high-precision positioning of the workpiece stage is obtained (the high-precision range generally requires accuracy to reach the sub-micron to nanometer level), and the second position deviation (the second position deviation is obtained by subtracting the positioning information fed back by the position sensor from the target position information, including the deviation caused by vibration) is further determined to be less than the preset threshold d. If the judgment conclusion is no, then the judgment result is that when the second position deviation is greater than or equal to the preset threshold, the workpiece stage has not moved to the vibration compensation range, and it is necessary to continue to control the movement of the workpiece stage, and repeat the step of determining whether it has moved to the vibration compensation range, until the judgment result is yes, that is, when the judgment result is that the second position deviation is less than the preset threshold, it is considered that the workpiece stage has moved to the vibration compensation range.

[0055] Step 403, when the workpiece stage moves to the vibration compensation range, the workpiece stage is controlled to move in a vibration form of a preset vibration relaxation model to determine a first position deviation during the movement of the workpiece stage;

[0056] Step 404, generating a scanning compensation signal based on the first position deviation;

[0057] Step 405 , performing electron beam scanning based on the scanning compensation signal, wherein the scanning compensation signal drives the electron beam to move relative to the workpiece stage during the electron beam scanning process.

[0058] For example, when the current position of the workpiece stage at time t1 is (x1, y1), the actual deflection position of the electron beam relative to the workpiece stage is also (x1, y1). That is, during the positioning movement of the workpiece stage, scanning imaging is performed simultaneously to achieve a compensation effect during the positioning process, thereby reducing the problem of image quality degradation caused by vibration in electron beam scanning imaging.

[0059] It is understandable that, in a stationary state, electron beam scanning is generally vector scanning. Figure 6 , attached Figure 6 This is a more commonly used progressive scanning mode, such as fast scanning in the row direction and slow scanning in the column direction. In order to ensure continuous compensation, the scanning compensation signal needs to superimpose the normal vector scanning signal with the workpiece stage displacement signal to ensure that the focus point of the compensated electron beam coincides with the position of the workpiece stage to be scanned, so as to achieve the compensation effect during the positioning process.

[0060] The scanning compensation method based on vibration relaxation of the present application controls the workpiece stage to move toward the target position according to the starting position and target position of the workpiece stage, so as to determine the second position deviation during the movement of the workpiece stage, and determines whether the workpiece stage moves to the vibration compensation range through the relationship between the second position deviation and the preset threshold. After the workpiece stage moves to the vibration compensation range, the workpiece stage is controlled to move in the vibration form of the preset vibration relaxation model, and during the vibration relaxation process of the workpiece stage, the electron beam movement is driven by generating a scanning compensation signal, thereby achieving the compensation effect in the positioning process; at the same time, since the compensation mechanism is started after the workpiece stage moves to the vibration compensation range, the position accuracy of the workpiece stage during the positioning process can be improved, the accuracy and effectiveness of each data in the compensation process are guaranteed, and the compensation effect in the positioning process is further improved.

[0061] The following is another specific implementation process of a scanning compensation method based on vibration relaxation provided by the present application. The method includes steps 501-506.

[0062] Step 501: Generate a positioning action instruction based on a start positioning signal.

[0063] Step 502, based on the positioning action instruction, control the movement of the workpiece stage and determine whether it moves to the vibration compensation range.

[0064] Step 503, control the workpiece stage to perform simulated motion to obtain the real-time position of the center of the workpiece stage at any time; determine the position deviation corresponding to any time based on the target position and the real-time position of the center of the workpiece stage at any time; and fit a vibration relaxation model consisting of time and position deviation according to any time and its corresponding position deviation.

[0065] It can be understood that the vibration relaxation model can be a functional relationship consisting of time and position deviation.

[0066] Step 504 , when the workpiece stage moves to the vibration compensation range, the workpiece stage is controlled to move in a vibration form of a preset vibration relaxation model to determine a first position deviation during the movement of the workpiece stage.

[0067] It is understandable that, with reference to Figure 2-3 As shown in the figure, during the workpiece stage positioning process, the first position deviation oscillates back and forth (may present positive or negative deviation, positive deviation is defined as crossing the target position, negative deviation is defined as not reaching the target position) in the process of approaching the 0 point (target position), and the amplitude decays over time, presenting a form similar to damped oscillation relaxation. According to the differences in the workpiece stage positioning control design, the common oscillation relaxation mode generally has two typical characteristics, one is as follows Figure 2 As shown, it oscillates back and forth around the 0 point; another form is as Figure 3 As shown, it approaches 0 in the form of overall negative deviation.

[0068] For both types, the relationship between the first position deviation and time can be expressed as the following functional relationship.

[0069] D = f(t), formula (1)

[0070] Where D is the first position deviation value, t is time, and function f is related to the mechanical characteristics, control characteristics, control algorithm, motion characteristics, etc. of the workpiece stage. For a fixed-design workpiece stage and control system, function f is correlated with the motion distance, motion speed, and acceleration during start and stop. Function f can be extracted from the mathematical form of the function by fitting experimental data, that is, function f is a vibration relaxation model composed of the fitted time and position deviation.

[0071] Specifically, after the electron beam imaging device is integrated and debugged, data on the vibration relaxation process can be collected through a large number of experiments, and then the functional relationship between the deviation value and the set parameters and time can be generated through data statistics and fitting to fit a vibration relaxation model consisting of time and position deviations.

[0072] For example, suppose the starting point coordinates are (x s ,y s ), the target point is (x0, y0). During the movement of the workpiece platform, at any time point t i The corresponding workpiece table coordinates (x i ,y i ) can be obtained by the position sensor, and the displacement of the workpiece stage relative to the target position can be represented by the vector: (Δx i ,Δy i )=(x i -x0,y i -y0). As time increases, (x i ,y i ) is closer to (x0,y0), that is, (Δx i ,Δy i ) approaches (0, 0). In the rectangular coordinate system, the deviation function D = f(t) can be decomposed into D along the x-axis x =f x (t) and along the y-axis D y =f y (t). By setting a higher sampling rate (sampling frequency >> relaxation oscillation frequency), the time and coordinate positioning deviation can be recorded as t i -Δx i ,t i -Δy i Two sets of data, using each set of data to fit the deviation function D x =f x (t), D y=f y (t).

[0073] by Figure 2 Taking the case where the workpiece stage oscillates back and forth near the target point as an example, in some cases the relaxation oscillation form presents a single-frequency sine wave characteristic. The deviation function can be expressed as:

[0074] D x =f x (t) = A x (t)sin(ωt+φ)+O x (t),

[0075] D y =f y (t) = A y (t)sin(ωt+φ)+O y (t),

[0076] Among them A x (t), A y (t) are x and y amplitude values, ω is the oscillation frequency, O x (t), O y (t) is the high-order term in the function, which accounts for a small proportion and is therefore discarded.

[0077] Common, according to the Fourier transform principle:

[0078]

[0079] The fitted deviation function can be expressed by several low-order terms of trigonometric functions:

[0080] D x =f x (t) = A x1 (t)sin(ω1t+φ1)+A x2 (t)sin(ω2t+φ2)+…Formula (2)

[0081] D y =f y (t) = A y1 (t)sin(ω1t+φ1)+A y2 (t)sin(ω2t+φ2)+…Formula (2)

[0082] In some embodiments, when the workpiece stage moves to the vibration compensation range, the workpiece stage controller controls the workpiece stage to move in the vibration form of the vibration relaxation model of formula (2) to drive the workpiece stage to approach the target position.

[0083] In some embodiments, when the workpiece stage has not moved to the vibration compensation range, the steps of controlling the movement of the workpiece stage based on the positioning action instruction and determining whether the workpiece stage has moved to the vibration compensation range are continued.

[0084] For example, when the workpiece stage moves to the vicinity of the vibration compensation range, the position sensor obtains the high-precision positioning of the workpiece stage (the high-precision range generally requires accuracy to reach the sub-micron to nanometer level), and the positioning control module determines whether the first position deviation (the first position deviation D is obtained by subtracting the positioning information fed back by the position sensor from the target position information, including the deviation caused by vibration) is less than a preset threshold d (the preset threshold d is also called the positioning window size) to further determine whether the workpiece stage moves to the vibration compensation range.

[0085] Step 505 , at any moment, based on the current first position deviation and a preset vibration compensation model, determine a vibration compensation parameter; determine a vibration compensation waveform according to the vibration compensation parameter; and generate a scanning compensation signal based on the vibration compensation waveform.

[0086] It can be understood that the preset vibration compensation model is a model that matches the above formula (2), which is used to determine the vibration compensation parameters to generate a scanning compensation signal. The scanning compensation signal can be an electric field, a magnetic field, or an electromagnetic field composite signal. The scanning compensation signal drives the imaging electron beam to move in the direction of the positioning deviation so that the moving distance is consistent with the size of the positioning deviation, thereby achieving a scanning compensation effect during the vibration relaxation process of the workpiece stage.

[0087] Further, generating a scanning compensation signal based on the vibration compensation waveform includes: performing signal amplification processing on the vibration compensation waveform; and generating the scanning compensation signal based on the vibration compensation waveform after the signal amplification processing.

[0088] Step 506 , performing electron beam scanning based on the scanning compensation signal, wherein the scanning compensation signal drives the electron beam to move relative to the workpiece stage during the electron beam scanning process.

[0089] The scanning compensation method based on vibration relaxation of the present application is based on controlling the workpiece stage to move in the vibration form of a preset vibration relaxation model when the workpiece stage moves to the vibration compensation range, so as to determine the first position deviation during the movement of the workpiece stage. Since the corresponding vibration compensation parameters in the preset vibration compensation model have a corresponding relationship with the corresponding position deviation in the vibration relaxation model, the vibration compensation parameters can be determined based on the first position deviation, the vibration compensation waveform can be determined based on the vibration compensation parameters, and the scanning compensation signal can be generated based on the vibration compensation waveform, thereby driving the electron beam movement through the scanning compensation signal during the vibration relaxation process of the workpiece stage to improve the accuracy of image compensation.

[0090] See attached Fig. 9As shown, the present application provides a scanning compensation system based on vibration relaxation, including: an industrial computer 910, used to generate a positioning action instruction based on a start positioning signal; a workpiece stage controller 920, used to control the movement of the workpiece stage based on the positioning action instruction and determine whether it moves to the vibration compensation range, and to control the workpiece stage to move in the vibration form of a preset vibration relaxation model when the workpiece stage moves to the vibration compensation range, so as to determine a first position deviation during the movement of the workpiece stage; a drive compensation module 930, used to generate a scanning compensation signal based on the first position deviation; and a scanning module 940, used to scan based on the scanning compensation signal, and the scanning compensation signal drives the electron beam to move relative to the workpiece stage during the electron beam scanning process.

[0091] In the vibration relaxation-based scanning compensation system of the present application, the compensation effect in the positioning process is achieved based on the cooperation among the industrial computer 910, the workpiece stage controller 920, the drive compensation module 930 and the scanning module 940.

[0092] In some embodiments, the drive compensation module 930 includes a dynamic compensation circuit module 931, a scanning waveform generator 932, a driving deflector 933, and a signal amplifier 935. The dynamic compensation circuit module 931 is configured with a vibration compensation model for determining a vibration compensation parameter based on the first position deviation; the scanning waveform generator 932 is used to determine a vibration compensation waveform based on the vibration compensation parameter; the driving deflector 933 is used to generate a scanning compensation signal based on the vibration compensation waveform; and the signal amplifier 935 is used to perform signal amplification processing on the vibration compensation waveform.

[0093] In some embodiments, the vibration relaxation-based scanning compensation system of the present application further includes a positioning signal processing circuit module (not shown), which is used to process the actual position information measured by the position sensor 122. The positioning signal processing circuit module can be an independent module or integrated into the workpiece stage controller 920.

[0094] In this embodiment, the industrial computer 910 generates a positioning action instruction based on the start positioning signal and sends it to the dynamic compensation circuit module 931 or the workpiece stage controller 920. The workpiece stage controller 920 drives the workpiece stage to move based on the positioning action instruction. The workpiece stage controller 920 or the dynamic compensation circuit module 931 controls the workpiece stage to move toward the target position based on the positioning signal processing circuit module, the starting position and the target position of the workpiece stage, and sends the position deviation signal to the drive compensation module 930. The drive compensation module 930 sends the vibration compensation signal to the scanning waveform generator 932 based on the above formula (2) and the position deviation signal. The scanning waveform generator 932 determines the vibration compensation waveform and drives the deflector 933 to generate the scanning compensation signal to realize the scanning compensation of the workpiece stage based on vibration relaxation.

[0095] In some embodiments, the driving compensation module 930 further includes a beam gate controller 934 for driving a beam gate, where the beam gate controller 934 is used to drive the beam gate to control whether the electron beam reaches the sample.

[0096] Again refer to the attached Figure 7 As shown, in some embodiments, the scanning module 940 in the vibration relaxation-based scanning compensation system of the present application also includes an electron beam scanning imaging device, which is used to perform electron beam imaging. Further, the electron beam scanning imaging device includes but is not limited to the following main parts: an electron beam scanning imaging module 100 for scanning imaging, including an electron gun 101, the electron gun 101 is used to generate an electron beam; a focusing lens (one or more) 102, used to adjust the degree of lens convergence; a beam gate 103, used to control whether the electron beam reaches the sample surface; an aberration controller (such as an stigmator) 104, used to control the electron beam imaging aberration; an aperture 105, used to control the electron beam spot and beam current; a detector 106, used to detect secondary electrons, backscattered electrons and generate image signals; an objective lens 107, used to converge the electron beam to the sample surface; a deflector 108, used to scan the electron beam; a sample 120 and a sample 120 for use. The workpiece stage 121 for carrying the sample (usually with two or more axes of freedom of movement); the position sensor 122 for positioning the workpiece stage (which can be implemented by a variety of mechanisms, including but not limited to laser interferometer distance sensor, grating ruler, capacitive distance sensor, photoelectric distance sensor, etc.); the vacuum chamber 130 for maintaining the vacuum state of the working environment, the vibration isolator 131 for suppressing and isolating external vibration; the equipment bracket 132 for supporting the main body of the equipment; the image signal processing circuit module 143 for image signal processing; the lens control module 144 for driving the lens; the electron gun control module and power supply 145 for controlling the electron gun; the aberration controller circuit module 146 for driving the aberration controller positioning signal processing. In addition, there are vacuum pump groups and connection components for obtaining vacuum, sample adsorption devices, sample conveying devices, power supplies, etc., which are not listed one by one in the figure because they are less relevant to the patent technology.

[0097] In some embodiments, the present application sets parameters such as starting point, speed or acceleration, etc. through the industrial computer 910 and the workpiece stage controller 920. The actual position information is measured by the position sensor 122 (based on which the first position deviation D is calculated), and the relevant data points are synchronized through the system clock to ensure real-time one-to-one matching.

[0098] It should be understood that the specific features, operations and details described hereinabove with respect to the method of the present application may also be similarly applied to the device and system of the present application, or vice versa. In addition, each step of the method of the present application described above may be performed by a corresponding component or unit of the device or system of the present application.

[0099] It should be understood that each module / unit of the device of the present application can be implemented in whole or in part by software, hardware, firmware or a combination thereof. Each module / unit can be embedded in the processor of the electronic device or independent of the processor in the form of hardware or firmware, or can be stored in the memory of the electronic device in the form of software for the processor to call to perform the operation of each module / unit. Each module / unit can be implemented as an independent component or module, or two or more modules / units can be implemented as a single component or module.

[0100] See attached Fig.10 As shown, the present application provides an electronic device 1000, which includes a processor 1010 and a memory 1020 storing computer program instructions. When the processor 1010 executes the computer program instructions, each step of the above-mentioned scanning compensation method based on vibration relaxation is implemented. The electronic device 1000 can be generally a server, a terminal, or any other electronic device with necessary computing and / or processing capabilities.

[0101] In one embodiment, the electronic device 1000 may include a processor, a memory, a network interface, a communication interface, etc. connected through a system bus. The processor of the electronic device 1000 may be used to provide necessary computing, processing and / or control capabilities. The memory of the electronic device 1000 may include a non-volatile storage medium and an internal memory. The non-volatile storage medium may store an operating system, a computer program, etc. The internal memory may provide an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface and the communication interface of the electronic device 1000 may be used to connect and communicate with external devices through a network. When the computer program is executed by the processor, the steps of the method of the present application are executed.

[0102] The present application provides a computer-readable storage medium, on which computer program instructions are stored. When the computer program instructions are executed by a processor, the above-mentioned scanning compensation method based on vibration relaxation is implemented.

[0103] Those skilled in the art will appreciate that the method steps of the present application can be completed by instructing related hardware such as the electronic device 1000 or a processor through a computer program, and the computer program can be stored in a non-temporary computer-readable storage medium, and the computer program causes the steps of the present application to be executed when it is executed. Depending on the circumstances, any reference to memory, storage, or other media herein may include non-volatile or volatile memory. Examples of non-volatile memory include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, magnetic tape, floppy disk, magneto-optical data storage device, optical data storage device, hard disk, solid state disk, etc. Examples of volatile memory include random access memory (RAM), external cache memory, etc.

[0104] The various technical features described above can be combined arbitrarily. Although all possible combinations of these technical features are not described, any combination of these technical features should be considered to be covered by this specification as long as there is no contradiction in such combination.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A scanning compensation method based on vibration relaxation, characterized in that: include: Based on the start positioning signal, a positioning action instruction is generated, wherein the positioning action instruction includes a starting position and a target position of the workpiece stage, wherein the starting position is the current position of the center of the workpiece stage, and the target position is the position of the center of the electron beam scanning field of view; Based on the positioning action instruction, the workpiece stage is controlled to move and determine whether it moves to the vibration compensation range, including: based on the starting position and the target position of the workpiece stage, the workpiece stage is controlled to move toward the target position to determine a second position deviation during the movement of the workpiece stage; when the second position deviation is less than a preset threshold, it is determined that the workpiece stage moves to the vibration compensation range; When the workpiece stage moves to the vibration compensation range, the workpiece stage is controlled to move in the vibration form of a preset vibration relaxation model to determine a first position deviation during the movement of the workpiece stage; including: in the process of controlling the workpiece stage to move in the vibration form of a preset vibration relaxation model, the current position of the center of the workpiece stage is acquired in real time; based on the current position of the center of the workpiece stage and the target position, the current first position deviation is determined; generating a scanning compensation signal based on the first position deviation; Electron beam scanning is performed based on the scanning compensation signal, and the scanning compensation signal drives the electron beam to move relative to the workpiece stage during the electron beam scanning process.

2. The scanning compensation method based on vibration relaxation according to claim 1, characterized in that: The vibration compensation range is determined based on a scanning range of the electron beam scanning field of view and a vibration range corresponding to the vibration relaxation model.

3. The scanning compensation method based on vibration relaxation according to claim 1, characterized in that: Before controlling the workpiece stage to move in a vibration form of a preset vibration relaxation model to determine a first position deviation during the movement of the workpiece stage, the method further includes: Control the workpiece stage to perform simulated motion to obtain the real-time position of the center of the workpiece stage at any time; Based on the target position and the real-time position of the center of the workpiece stage at any time, determine the position deviation corresponding to any time; According to any moment and its corresponding position deviation, the vibration relaxation model consisting of time and position deviation is fitted.

4. The scanning compensation method based on vibration relaxation according to claim 1, characterized in that: The step of generating a scanning compensation signal based on the first position deviation comprises: At any moment, determining a vibration compensation parameter based on the current first position deviation and a preset vibration compensation model; Determining a vibration compensation waveform according to the vibration compensation parameters; Based on the vibration compensation waveform, a scanning compensation signal is generated.

5. The scanning compensation method based on vibration relaxation according to claim 4, characterized in that: Before generating a scanning compensation signal based on the first position deviation, the method further includes: Based on the vibration relaxation model, the vibration compensation model is determined, wherein a corresponding vibration compensation parameter in the vibration compensation model has a corresponding relationship with a corresponding position deviation in the vibration relaxation model.

6. A scanning compensation system based on vibration relaxation, characterized in that: include: The industrial computer is used to generate a positioning action instruction based on the start positioning signal, wherein the positioning action instruction includes a starting position and a target position of the workpiece stage, wherein the starting position is the current position of the center of the workpiece stage, and the target position is the position of the center of the electron beam scanning field of view; A workpiece stage controller, for controlling the movement of the workpiece stage and determining whether it moves to the vibration compensation range based on the positioning action instruction, including: based on the starting position and target position of the workpiece stage, controlling the workpiece stage to move toward the target position to determine a second position deviation during the movement of the workpiece stage; when the second position deviation is less than a preset threshold, determining that the workpiece stage moves to the vibration compensation range; and for controlling the workpiece stage to move in the vibration form of a preset vibration relaxation model when the workpiece stage moves to the vibration compensation range to determine a first position deviation during the movement of the workpiece stage; including: in the process of controlling the workpiece stage to move in the vibration form of a preset vibration relaxation model, acquiring the current position of the center of the workpiece stage in real time; determining the current first position deviation based on the current position of the center of the workpiece stage and the target position; a driving compensation module, configured to generate a scanning compensation signal based on the first position deviation; and The scanning module is used to perform scanning based on the scanning compensation signal, wherein the scanning compensation signal drives the electron beam to move relative to the workpiece stage during the electron beam scanning process.

7. The scanning compensation system based on vibration relaxation according to claim 6, characterized in that: The driving compensation module includes a dynamic compensation circuit module, a scanning waveform generator and a driving deflector; The dynamic compensation circuit module is configured with a vibration compensation model for determining vibration compensation parameters based on the first position deviation; The scanning waveform generator is used to determine a vibration compensation waveform based on the vibration compensation parameter; The driving deflector is used to generate a scanning compensation signal based on the vibration compensation waveform.

8. An electronic device, characterized in that: include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include a method for executing the vibration relaxation-based scanning compensation method described in any one of claims 1 to 5.

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